[clang] [CLANG][AArch64] Add the modal 8 bit floating-point scalar type (PR #97277)

[LLVM Continuous Integration via cfe-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `arc-builder` running on `arc-worker` while building `clang` at step 6 "test-build-unified-tree-check-all".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/3/builds/6669

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

```
Step 6 (test-build-unified-tree-check-all) failure: test (failure)
******************** TEST 'Clang :: CodeGen/aarch64-debug-types.c' FAILED ********************
Exit Code: 1

Command Output (stderr):
--
RUN: at line 1: /buildbot/worker/arc-folder/build/bin/clang -cc1 -internal-isystem /buildbot/worker/arc-folder/build/lib/clang/20/include -nostdsysteminc -triple aarch64-none-linux-gnu -target-feature +neon  -target-feature +fp8   -emit-llvm -o - /buildbot/worker/arc-folder/llvm-project/clang/test/CodeGen/aarch64-debug-types.c -debug-info-kind=limited 2>&1 | /buildbot/worker/arc-folder/build/bin/FileCheck /buildbot/worker/arc-folder/llvm-project/clang/test/CodeGen/aarch64-debug-types.c
+ /buildbot/worker/arc-folder/build/bin/FileCheck /buildbot/worker/arc-folder/llvm-project/clang/test/CodeGen/aarch64-debug-types.c
+ /buildbot/worker/arc-folder/build/bin/clang -cc1 -internal-isystem /buildbot/worker/arc-folder/build/lib/clang/20/include -nostdsysteminc -triple aarch64-none-linux-gnu -target-feature +neon -target-feature +fp8 -emit-llvm -o - /buildbot/worker/arc-folder/llvm-project/clang/test/CodeGen/aarch64-debug-types.c -debug-info-kind=limited
/buildbot/worker/arc-folder/llvm-project/clang/test/CodeGen/aarch64-debug-types.c:6:16: error: CHECK-DAG: expected string not found in input
 // CHECK-DAG: !DIDerivedType(tag: DW_TAG_typedef, name: "__MFloat8_t", {{.*}}, baseType: ![[ELTTYU8:[0-9]+]]
               ^
<stdin>:1:1: note: scanning from here
/buildbot/worker/arc-folder/llvm-project/clang/test/CodeGen/aarch64-debug-types.c:3:9: fatal error: 'arm_neon.h' file not found
^

Input file: <stdin>
Check file: /buildbot/worker/arc-folder/llvm-project/clang/test/CodeGen/aarch64-debug-types.c

-dump-input=help explains the following input dump.

Input was:
<<<<<<
       1: /buildbot/worker/arc-folder/llvm-project/clang/test/CodeGen/aarch64-debug-types.c:3:9: fatal error: 'arm_neon.h' file not found 
dag:6     X~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ error: no match found
       2:  3 | #include<arm_neon.h> 
dag:6     ~~~~~~~~~~~~~~~~~~~~~~~~~~
       3:  | ^~~~~~~~~~~~ 
dag:6     ~~~~~~~~~~~~~~~~
       4: 1 error generated. 
dag:6     ~~~~~~~~~~~~~~~~~~~
>>>>>>

--

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


```

</details>

https://github.com/llvm/llvm-project/pull/97277