[clang] [llvm] [AArch64] Add FEAT_SME_B16B16 and remove FEAT_B16B16 (PR #102501)

[LLVM Continuous Integration via cfe-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `clang-aarch64-quick` running on `linaro-clang-aarch64-quick` while building `clang,llvm` at step 5 "ninja check 1".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/65/builds/2630

Here is the relevant piece of the build log for the reference:
```
Step 5 (ninja check 1) failure: stage 1 checked (failure)
******************** TEST 'Clangd Unit Tests :: ./ClangdTests/248/313' FAILED ********************
Script(shard):
--
GTEST_OUTPUT=json:/home/tcwg-buildbot/worker/clang-aarch64-quick/stage1/tools/clang/tools/extra/clangd/unittests/./ClangdTests-Clangd Unit Tests-1928594-248-313.json GTEST_SHUFFLE=0 GTEST_TOTAL_SHARDS=313 GTEST_SHARD_INDEX=248 /home/tcwg-buildbot/worker/clang-aarch64-quick/stage1/tools/clang/tools/extra/clangd/unittests/./ClangdTests
--

Note: This is test shard 249 of 313.
[==========] Running 4 tests from 4 test suites.
[----------] Global test environment set-up.
[----------] 1 test from CommandMangler
[ RUN      ] CommandMangler.ClangPath
[       OK ] CommandMangler.ClangPath (5 ms)
[----------] 1 test from CommandMangler (5 ms total)

[----------] 1 test from GlobalCompilationDatabaseTest
[ RUN      ] GlobalCompilationDatabaseTest.FallbackCommand
[       OK ] GlobalCompilationDatabaseTest.FallbackCommand (7 ms)
[----------] 1 test from GlobalCompilationDatabaseTest (7 ms total)

[----------] 1 test from CrossFileRenameTests
[ RUN      ] CrossFileRenameTests.ObjC
ASTWorker building file /clangd-test/foo.h version null with command 
[/clangd-test]
clang -xobjective-c /clangd-test/foo.h
Driver produced command: cc1 -cc1 -triple aarch64-unknown-linux-gnu -fsyntax-only -disable-free -clear-ast-before-backend -main-file-name foo.h -mrelocation-model pic -pic-level 2 -pic-is-pie -mframe-pointer=non-leaf -fmath-errno -ffp-contract=on -fno-rounding-math -mconstructor-aliases -funwind-tables=2 -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/20 -internal-isystem lib/clang/20/include -internal-isystem /usr/local/include -internal-externc-isystem /include -internal-externc-isystem /usr/include -ferror-limit 19 -fno-signed-char -fgnuc-version=4.2.1 -fskip-odr-check-in-gmf -fobjc-runtime=gcc -fobjc-encode-cxx-class-template-spec -fobjc-exceptions -no-round-trip-args -target-feature -fmv -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -x objective-c /clangd-test/foo.h
Building first preamble for /clangd-test/foo.h version null
Built preamble of size 696836 for file /clangd-test/foo.h version null in 0.10 seconds
indexed preamble AST for /clangd-test/foo.h version null:
  symbol slab: 0 symbols, 120 bytes
  ref slab: 0 symbols, 0 refs, 128 bytes
  relations slab: 0 relations, 24 bytes
indexed file AST for /clangd-test/foo.h version null:
  symbol slab: 2 symbols, 4680 bytes
  ref slab: 2 symbols, 2 refs, 4272 bytes
  relations slab: 0 relations, 24 bytes
Build dynamic index for main-file symbols with estimated memory usage of 12040 bytes
ASTWorker building file /clangd-test/foo.m version null with command 
[/clangd-test]
clang -xobjective-c /clangd-test/foo.m
Driver produced command: cc1 -cc1 -triple aarch64-unknown-linux-gnu -fsyntax-only -disable-free -clear-ast-before-backend -main-file-name foo.m -mrelocation-model pic -pic-level 2 -pic-is-pie -mframe-pointer=non-leaf -fmath-errno -ffp-contract=on -fno-rounding-math -mconstructor-aliases -funwind-tables=2 -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/20 -internal-isystem lib/clang/20/include -internal-isystem /usr/local/include -internal-externc-isystem /include -internal-externc-isystem /usr/include -ferror-limit 19 -fno-signed-char -fgnuc-version=4.2.1 -fskip-odr-check-in-gmf -fobjc-runtime=gcc -fobjc-encode-cxx-class-template-spec -fobjc-exceptions -no-round-trip-args -target-feature -fmv -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -x objective-c /clangd-test/foo.m
Building first preamble for /clangd-test/foo.m version null
Built preamble of size 696836 for file /clangd-test/foo.m version null in 0.06 seconds
indexed preamble AST for /clangd-test/foo.m version null:
  symbol slab: 0 symbols, 120 bytes
  ref slab: 0 symbols, 0 refs, 128 bytes
  relations slab: 0 relations, 24 bytes
indexed file AST for /clangd-test/foo.m version null:
  symbol slab: 2 symbols, 4680 bytes
  ref slab: 2 symbols, 3 refs, 4272 bytes
  relations slab: 0 relations, 24 bytes
...

```

https://github.com/llvm/llvm-project/pull/102501