mem-ruby: Removed invalid transition from MOESI_CMP dir

mem-ruby: Removed invalid transition from MOESI_CMP dir

When memory data is received we always have a valid directory
entry or are in a transient state.

Change-Id: I0e9120e320c157fd306909458cbc446275a4f738
Signed-off-by: Tiago Mück <tiago.muck@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/27848
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Reviewed-by: Pouya Fotouhi <pfotouhi@ucdavis.edu>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Tested-by: Gem5 Cloud Project GCB service account <345032938727@cloudbuild.gserviceaccount.com>