[llvm] [MCA] Ignore host -mcpu when target lacks said CPU (PR #174004)

[Vladimir Vereschaka via llvm-commits]

vvereschaka wrote:

Hi @Amichaxx ,

the test still gets failed on the NVPTX Ubuntu builders:
* https://lab.llvm.org/staging/#/builders/153/builds/23
* https://lab.llvm.org/staging/#/builders/116/builds/23

```
******************** TEST 'LLVM :: tools/llvm-mca/invalid_input_file_name.test' FAILED ********************
Exit Code: 2
Command Output (stdout):
--
# RUN: at line 1
not /home/buildbot/worker/as-builder-7/llvm-nvptx-nvidia-ubuntu/build/bin/llvm-mca /home/buildbot/worker/as-builder-7/llvm-nvptx-nvidia-ubuntu/build/test/tools/llvm-mca/Output/invalid_input_file_name.test.tmp.blah -o /dev/null 2>&1 | /home/buildbot/worker/as-builder-7/llvm-nvptx-nvidia-ubuntu/build/bin/FileCheck -DMSG='No such file or directory' --check-prefix=ENOENT /home/buildbot/worker/as-builder-7/llvm-nvptx-nvidia-ubuntu/llvm-project/llvm/test/tools/llvm-mca/invalid_input_file_name.test
# executed command: not /home/buildbot/worker/as-builder-7/llvm-nvptx-nvidia-ubuntu/build/bin/llvm-mca /home/buildbot/worker/as-builder-7/llvm-nvptx-nvidia-ubuntu/build/test/tools/llvm-mca/Output/invalid_input_file_name.test.tmp.blah -o /dev/null
# executed command: /home/buildbot/worker/as-builder-7/llvm-nvptx-nvidia-ubuntu/build/bin/FileCheck '-DMSG=No such file or directory' --check-prefix=ENOENT /home/buildbot/worker/as-builder-7/llvm-nvptx-nvidia-ubuntu/llvm-project/llvm/test/tools/llvm-mca/invalid_input_file_name.test
# .---command stderr------------
# | FileCheck error: '<stdin>' is empty.
# | FileCheck command line:  /home/buildbot/worker/as-builder-7/llvm-nvptx-nvidia-ubuntu/build/bin/FileCheck -DMSG=No such file or directory --check-prefix=ENOENT /home/buildbot/worker/as-builder-7/llvm-nvptx-nvidia-ubuntu/llvm-project/llvm/test/tools/llvm-mca/invalid_input_file_name.test
# `-----------------------------
# error: command failed with exit status: 2

```

https://github.com/llvm/llvm-project/pull/174004