[llvm] [msan][NFCI] Remove element-size override for VNNI intrinsics (PR #172762)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `llvm-clang-x86_64-sie-win` running on `sie-win-worker` while building `llvm` at step 7 "test-build-unified-tree-check-all".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/46/builds/28118

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

```
Step 7 (test-build-unified-tree-check-all) failure: test (failure)
******************** TEST 'Clang :: Preprocessor/embed_preprocess_to_file.c' FAILED ********************
Exit Code: 1

Command Output (stdout):
--
# RUN: at line 1
z:\b\llvm-clang-x86_64-sie-win\build\bin\clang.exe -cc1 -internal-isystem Z:\b\llvm-clang-x86_64-sie-win\build\lib\clang\22\include -nostdsysteminc -std=c23 Z:\b\llvm-clang-x86_64-sie-win\llvm-project\clang\test\Preprocessor\embed_preprocess_to_file.c -E --embed-dir=Z:\b\llvm-clang-x86_64-sie-win\llvm-project\clang\test\Preprocessor/Inputs | z:\b\llvm-clang-x86_64-sie-win\build\bin\filecheck.exe Z:\b\llvm-clang-x86_64-sie-win\llvm-project\clang\test\Preprocessor\embed_preprocess_to_file.c --check-prefix EXPANDED
# executed command: 'z:\b\llvm-clang-x86_64-sie-win\build\bin\clang.exe' -cc1 -internal-isystem 'Z:\b\llvm-clang-x86_64-sie-win\build\lib\clang\22\include' -nostdsysteminc -std=c23 'Z:\b\llvm-clang-x86_64-sie-win\llvm-project\clang\test\Preprocessor\embed_preprocess_to_file.c' -E '--embed-dir=Z:\b\llvm-clang-x86_64-sie-win\llvm-project\clang\test\Preprocessor/Inputs'
# note: command had no output on stdout or stderr
# executed command: 'z:\b\llvm-clang-x86_64-sie-win\build\bin\filecheck.exe' 'Z:\b\llvm-clang-x86_64-sie-win\llvm-project\clang\test\Preprocessor\embed_preprocess_to_file.c' --check-prefix EXPANDED
# .---command stderr------------
# | Z:\b\llvm-clang-x86_64-sie-win\llvm-project\clang\test\Preprocessor\embed_preprocess_to_file.c:10:14: error: EXPANDED: expected string not found in input
# | // EXPANDED: const char data[] = {'h',106 , 'a', 0};
# |              ^
# | <stdin>:1:1: note: scanning from here
# | # 1 "Z:\\b\\llvm-clang-x86_64-sie-win\\llvm-project\\clang\\test\\Preprocessor\\embed_preprocess_to_file.c"
# | ^
# | <stdin>:13:1: note: possible intended match here
# | const char data[] = {'h',106 , 'a', 0
# | ^
# | 
# | Input file: <stdin>
# | Check file: Z:\b\llvm-clang-x86_64-sie-win\llvm-project\clang\test\Preprocessor\embed_preprocess_to_file.c
# | 
# | -dump-input=help explains the following input dump.
# | 
# | Input was:
# | <<<<<<
# |             1: # 1 "Z:\\b\\llvm-clang-x86_64-sie-win\\llvm-project\\clang\\test\\Preprocessor\\embed_preprocess_to_file.c" 
# | check:10'0     X~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ error: no match found
# |             2: # 1 "<built-in>" 1 
# | check:10'0     ~~~~~~~~~~~~~~~~~~~
# |             3: # 1 "<built-in>" 3 
# | check:10'0     ~~~~~~~~~~~~~~~~~~~
# |             4: # 421 "<built-in>" 3 
# | check:10'0     ~~~~~~~~~~~~~~~~~~~~~
# |             5: # 1 "<command line>" 1 
# | check:10'0     ~~~~~~~~~~~~~~~~~~~~~~~
# |             6: # 1 "<built-in>" 2 
# | check:10'0     ~~~~~~~~~~~~~~~~~~~
# |             7: # 1 "Z:\\b\\llvm-clang-x86_64-sie-win\\llvm-project\\clang\\test\\Preprocessor\\embed_preprocess_to_file.c" 2 
# | check:10'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# |             8:  
# | check:10'0     ~
# |             9:  
# | check:10'0     ~
# |            10:  
# | check:10'0     ~
# |            11:  
# | check:10'0     ~
...

```

</details>

https://github.com/llvm/llvm-project/pull/172762