[llvm] [SelectionDAG] Add computeKnownBits for ISD::ROTL/ROTR. (PR #156142)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `clang-aarch64-global-isel` running on `linaro-clang-aarch64-global-isel` while building `llvm` at step 7 "ninja check 1".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/125/builds/10125

<details>
<summary>Here is the relevant piece of the build log for the reference</summary>

```
Step 7 (ninja check 1) failure: stage 1 checked (failure)
******************** TEST 'Clangd Unit Tests :: ./ClangdTests/4/21' FAILED ********************
Script(shard):
--
GTEST_OUTPUT=json:/home/tcwg-buildbot/worker/clang-aarch64-global-isel/stage1/tools/clang/tools/extra/clangd/unittests/./ClangdTests-Clangd Unit Tests-2432776-4-21.json GTEST_SHUFFLE=0 GTEST_TOTAL_SHARDS=21 GTEST_SHARD_INDEX=4 /home/tcwg-buildbot/worker/clang-aarch64-global-isel/stage1/tools/clang/tools/extra/clangd/unittests/./ClangdTests
--

Note: This is test shard 5 of 21.
[==========] Running 63 tests from 52 test suites.
[----------] Global test environment set-up.
[----------] 1 test from ClangdAST
[ RUN      ] ClangdAST.PrintType
Built preamble of size 707660 for file /clangd-test/TestTU.cpp version null in 0.08 seconds
Built preamble of size 707660 for file /clangd-test/TestTU.cpp version null in 0.03 seconds
[       OK ] ClangdAST.PrintType (144 ms)
[----------] 1 test from ClangdAST (144 ms total)

[----------] 1 test from BackgroundQueueTest
[ RUN      ] BackgroundQueueTest.Boost
[       OK ] BackgroundQueueTest.Boost (0 ms)
[----------] 1 test from BackgroundQueueTest (0 ms total)

[----------] 1 test from ClangdServerTest
[ RUN      ] ClangdServerTest.PropagatesContexts
ASTWorker building file /clangd-test/foo.cpp version null with command 
[/clangd-test]
clang -ffreestanding /clangd-test/foo.cpp
Driver produced command: cc1 -cc1 -triple aarch64-unknown-linux-gnu -fsyntax-only -disable-free -clear-ast-before-backend -main-file-name foo.cpp -mrelocation-model pic -pic-level 2 -pic-is-pie -mframe-pointer=non-leaf -fmath-errno -ffp-contract=on -fno-rounding-math -mconstructor-aliases -ffreestanding -enable-tlsdesc -target-cpu generic -target-feature +v8a -target-feature +fp-armv8 -target-feature +neon -target-abi aapcs -debugger-tuning=gdb -fdebug-compilation-dir=/clangd-test -fcoverage-compilation-dir=/clangd-test -resource-dir lib/clang/22 -internal-isystem lib/clang/22/include -internal-isystem /usr/local/include -internal-externc-isystem /include -internal-externc-isystem /usr/include -fdeprecated-macro -ferror-limit 19 -fno-signed-char -fgnuc-version=4.2.1 -fskip-odr-check-in-gmf -fcxx-exceptions -fexceptions -no-round-trip-args -target-feature -fmv -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -x c++ /clangd-test/foo.cpp
Building first preamble for /clangd-test/foo.cpp version null
Built preamble of size 736852 for file /clangd-test/foo.cpp version null in 0.44 seconds
[       OK ] ClangdServerTest.PropagatesContexts (494 ms)
[----------] 1 test from ClangdServerTest (494 ms total)

[----------] 1 test from ClangdServer
[ RUN      ] ClangdServer.InactiveRegions
ASTWorker building file /clangd-test/foo.cpp version null with command 
[/clangd-test]
clang -ffreestanding -DCMDMACRO /clangd-test/foo.cpp
Driver produced command: cc1 -cc1 -triple aarch64-unknown-linux-gnu -fsyntax-only -disable-free -clear-ast-before-backend -main-file-name foo.cpp -mrelocation-model pic -pic-level 2 -pic-is-pie -mframe-pointer=non-leaf -fmath-errno -ffp-contract=on -fno-rounding-math -mconstructor-aliases -ffreestanding -enable-tlsdesc -target-cpu generic -target-feature +v8a -target-feature +fp-armv8 -target-feature +neon -target-abi aapcs -debugger-tuning=gdb -fdebug-compilation-dir=/clangd-test -fcoverage-compilation-dir=/clangd-test -resource-dir lib/clang/22 -D CMDMACRO -internal-isystem lib/clang/22/include -internal-isystem /usr/local/include -internal-externc-isystem /include -internal-externc-isystem /usr/include -fdeprecated-macro -ferror-limit 19 -fno-signed-char -fgnuc-version=4.2.1 -fskip-odr-check-in-gmf -fcxx-exceptions -fexceptions -no-round-trip-args -target-feature -fmv -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -x c++ /clangd-test/foo.cpp
Building first preamble for /clangd-test/foo.cpp version null
Built preamble of size 737156 for file /clangd-test/foo.cpp version null in 0.16 seconds
[       OK ] ClangdServer.InactiveRegions (178 ms)
[----------] 1 test from ClangdServer (178 ms total)

[----------] 6 tests from CompletionTest
[ RUN      ] CompletionTest.InjectedTypename
Built preamble of size 707644 for file /clangd-test/foo.cpp version null in 0.05 seconds
Code complete: sema context DotMemberAccess, query scopes [] (AnyScope=false), expected type <none>
Code complete: 0 results from Sema, 0 from Index, 0 matched, 0 from identifiers, 0 returned.
Built preamble of size 707644 for file /clangd-test/foo.cpp version null in 0.03 seconds
Code complete: sema context ArrowMemberAccess, query scopes [] (AnyScope=false), expected type <none>
...

```

</details>

https://github.com/llvm/llvm-project/pull/156142