[llvm] [BOLT][NFC] Unify two symbol table iterations (PR #90724)

[Donghee Na via llvm-commits]

corona10 wrote:

@aaupov 
Anyway my observation is noisy level changes :) (Even clang or CPython)

AS-IS
---User Time---   --System Time--   --User+System--   ---Wall Time---  --- Name ---   
0.0000 (  0.1%)   0.0000 (  0.1%)   0.0000 (  0.1%)   0.0000 (  0.1%)  discover file objects

TO-BE
---User Time---   --System Time--   --User+System--   ---Wall Time---  --- Name ---                  
0.0000 (  0.0%)   0.0000 (  0.1%)   0.0000 (  0.1%)   0.0000 (  0.0%)  discover file objects

https://github.com/llvm/llvm-project/pull/90724