[llvm] [BOLT][AArch64] Fixed indirect call instrumentation snippet (PR #141918)

[Paschalis Mpeis via llvm-commits]

paschalis-mpeis wrote:

Shall we also check the entry / exit stubs in the amended lit test?
ie objdump and check code output of `__bolt_instr _ind_call_handler`, `bolt_instr_ind_call_handler_func`

We could also check the BOLT output, probably with:
> BOLT-INSTRUMENTER: Number of indirect call site descriptors: N

https://github.com/llvm/llvm-project/pull/141918