[BOLT] Add constant island check in scanExternalRefs()#165577

Jinjie-Huang merged 2 commits intollvm:mainllvm/llvm-project:mainfrom

Jinjie-Huang:users/huangjinjie/ignore_entry_pointJinjie-Huang/llvm-project:users/huangjinjie/ignore_entry_pointCopy head branch name to clipboard