[llvm] [ProfileData] Implement contains in SampleProfileNameTable (NFC) (PR #211995)

[Martin Storsjö via llvm-commits]

mstorsjo wrote:

This broke building for 32 bit platforms, e.g. https://github.com/mstorsjo/llvm-mingw/actions/runs/30506767557/job/90782825838:
```

In file included from /home/runner/work/llvm-mingw/llvm-mingw/llvm-project/llvm/lib/ProfileData/SampleProfReader.cpp:22:
/home/runner/work/llvm-mingw/llvm-mingw/llvm-project/llvm/include/llvm/ProfileData/SampleProfReader.h:507:23: error: non-constant-expression cannot be narrowed from type 'uint64_t' (aka 'unsigned long long') to 'size_t' (aka 'unsigned int') in initializer list [-Wc++11-narrowing]
  507 |         Spans{{{Data, NumCS},
      |                       ^~~~~
/home/runner/work/llvm-mingw/llvm-mingw/llvm-project/llvm/include/llvm/ProfileData/SampleProfReader.h:507:23: note: insert an explicit cast to silence this issue
  507 |         Spans{{{Data, NumCS},
      |                       ^~~~~
      |                       static_cast<size_t>( )
/home/runner/work/llvm-mingw/llvm-mingw/llvm-project/llvm/include/llvm/ProfileData/SampleProfReader.h:508:31: error: non-constant-expression cannot be narrowed from type 'uint64_t' (aka 'unsigned long long') to 'size_t' (aka 'unsigned int') in initializer list [-Wc++11-narrowing]
  508 |                {Data + NumCS, NumFlat},
      |                               ^~~~~~~
/home/runner/work/llvm-mingw/llvm-mingw/llvm-project/llvm/include/llvm/ProfileData/SampleProfReader.h:508:31: note: insert an explicit cast to silence this issue
  508 |                {Data + NumCS, NumFlat},
      |                               ^~~~~~~
      |                               static_cast<size_t>( )
/home/runner/work/llvm-mingw/llvm-mingw/llvm-project/llvm/include/llvm/ProfileData/SampleProfReader.h:509:41: error: non-constant-expression cannot be narrowed from type 'uint64_t' (aka 'unsigned long long') to 'size_t' (aka 'unsigned int') in initializer list [-Wc++11-narrowing]
  509 |                {Data + NumCS + NumFlat, NumInlinees}}} {}
      |                                         ^~~~~~~~~~~
/home/runner/work/llvm-mingw/llvm-mingw/llvm-project/llvm/include/llvm/ProfileData/SampleProfReader.h:509:41: note: insert an explicit cast to silence this issue
  509 |                {Data + NumCS + NumFlat, NumInlinees}}} {}
      |                                         ^~~~~~~~~~~
      |                                         static_cast<size_t>( )
3 errors generated.
```

https://github.com/llvm/llvm-project/pull/211995