x86: Switch from MessageReq and Resp to WriteReq and Resp.
Originally MessageReq was intended to mark a packet as a holding a
message destined for a particular recipient and which would not
interact with other packets.
This is similar to the way a WriteReq would behave if writing to a
device register which needs to be updated atomically. Also, while the
memory system *could* recognize a MessageReq and know that it didn't
need to interact with other packets, that was never implemented.
Change-Id: Ie54301d1d8820e206d6bae96e200ae8c71d2d784
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/20823
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>