[lld] [lld] Merge equivalent symbols found during ICF (PR #134342)

[Fangrui Song via llvm-commits]

================
@@ -0,0 +1,94 @@
+// REQUIRES: aarch64
----------------
MaskRay wrote:

As you've switched to `#`, switch to `# REQUIRES: aarch64` as well.
While here, can you add a file-level comment about the purpose of the test? Use `## `

https://github.com/llvm/llvm-project/pull/134342