Revert D108432 "[InstrProfiling] Keep profd non-private for non-renamable comdat functions"

This reverts commit f653beea.

It broke Windows coverage-inline.cpp because link.exe has a limitation
that external symbols in IMAGE_COMDAT_SELECT_ASSOCIATIVE don't work.

It essentially dropped the previous size optimization for coverage
because coverage doesn't rename comdat by default.
Needs more investigation what we should do.