misc: Use compiler.hh macros when available.
Some places were hand coding __attribute__s when macros in compiler.hh
were available to do that job. Using the macros helps abstract away
compiler specific details and should be used when possible.
Change-Id: I94befebcfde2d673e874e9959588f69781bd9021
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/35975
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Maintainer: Gabe Black <gabeblack@google.com>
Tested-by: kokoro <noreply+kokoro@google.com>