[llvm] [BOLT] Add support for safe-icf (PR #116275)

[Amir Ayupov via llvm-commits]

================
@@ -2,7 +2,7 @@
 # RUN: ld.lld %t.o -o %t.so --shared --entry=func1.cold.1 --emit-relocs
 # RUN: llvm-bolt -relocs %t.so -o %t -reorder-functions=hfsort+ \
 # RUN:    -split-functions -reorder-blocks=ext-tsp -split-all-cold \
-# RUN:    -dyno-stats -icf=1 -use-gnu-stack
----------------
aaupov wrote:

Then please update all the places where we have `icf=1` ourselves (internal uses, in-tree tests, binary tests). But I think it's better not to screw our users without a warning.

https://github.com/llvm/llvm-project/pull/116275