[clang] [clang-tools-extra] FunctionDecl::getFunctionTypeLoc: ignore function type attributes (PR #118420)

[LLVM Continuous Integration via cfe-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `clang-armv7-global-isel` running on `linaro-clang-armv7-global-isel` while building `clang-tools-extra,clang` at step 7 "ninja check 1".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/39/builds/5722

<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 'Clang-Unit :: AST/./ASTTests/9/15' FAILED ********************
Script(shard):
--
GTEST_OUTPUT=json:/home/tcwg-buildbot/worker/clang-armv7-global-isel/stage1/tools/clang/unittests/AST/./ASTTests-Clang-Unit-2672158-9-15.json GTEST_SHUFFLE=0 GTEST_TOTAL_SHARDS=15 GTEST_SHARD_INDEX=9 /home/tcwg-buildbot/worker/clang-armv7-global-isel/stage1/tools/clang/unittests/AST/./ASTTests
--

Script:
--
/home/tcwg-buildbot/worker/clang-armv7-global-isel/stage1/tools/clang/unittests/AST/./ASTTests --gtest_filter=Attr.AnnotateType
--
input.cc:16:20: warning: 'preserve_most' calling convention is not supported for this target [-Wignored-attributes]
   16 |     __attribute__((preserve_most)) int f_cc_preserve_most();
      |                    ^
input.cc:19:5: warning: 'preserve_most' calling convention is not supported for this target [-Wignored-attributes]
   19 |     PRESERVE_MOST int f_macro_attribue();
      |     ^
input.cc:18:42: note: expanded from macro 'PRESERVE_MOST'
   18 |     #define PRESERVE_MOST __attribute__((preserve_most))
      |                                          ^
input.cc:21:25: warning: 'preserve_most' calling convention is not supported for this target [-Wignored-attributes]
   21 |     int (__attribute__((preserve_most)) f_paren_attribute)();
      |                         ^
input.cc:24:7: warning: 'preserve_most' calling convention is not supported for this target [-Wignored-attributes]
   24 |       PRESERVE_MOST
      |       ^
input.cc:18:42: note: expanded from macro 'PRESERVE_MOST'
   18 |     #define PRESERVE_MOST __attribute__((preserve_most))
      |                                          ^
../llvm/clang/unittests/AST/AttrTest.cpp:186: Failure
Value of: FT->getCallConv() == CC_PreserveMost
  Actual: false
Expected: true

O: f_macro_attribue
O: f_paren_attribute
O: f_w_paren_and_attr

../llvm/clang/unittests/AST/AttrTest.cpp:186
Value of: FT->getCallConv() == CC_PreserveMost
  Actual: false
Expected: true



********************


```

</details>

https://github.com/llvm/llvm-project/pull/118420