gpu-compute, mem-ruby: Add p_popRequestQueue to some transitions

Two W->WI transitions, on events RdBlk and Atomic in the GPU L2 cache
coherence protocol do not clear  the request from the request queue upon
completing the transition. This action is not performed in the respone
path. This update adds the p_popRequestQueue action to each of these
transitions to remove the stale request from the queue.

Change-Id: Ia2679fe3dd702f4df2bc114f4607ba40c18d6ff1
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/67192
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>

src/mem/ruby/protocol/GPU_VIPER-TCC.sm

@@ -721,6 +721,7 @@ machine(MachineType:TCC, "TCC Cache")
     p_profileHit;
     t_allocateTBE;
     wb_writeBack;
+    p_popRequestQueue;
   }
 
   transition(I, RdBlk, IV) {TagArrayRead} {
@@ -815,6 +816,7 @@ transition(I, Atomic, A) {TagArrayRead} {
     p_profileHit;
     t_allocateTBE;
     wb_writeBack;
+    p_popRequestQueue;
   }
 
   transition(I, WrVicBlk) {TagArrayRead} {