cris: Handle opcode zero

It's a valid branch pc + 2.

Signed-off-by: Edgar E. Iglesias <edgar.iglesias@gmail.com>
diff --git a/target-cris/translate_v10.c b/target-cris/translate_v10.c
index 5b14157..637ac20 100644
--- a/target-cris/translate_v10.c
+++ b/target-cris/translate_v10.c
@@ -262,9 +262,6 @@
             break;
 
         case CRISV10_QIMM_BCC_R0:
-            if (!dc->ir) {
-                cpu_abort(dc->env, "opcode zero\n");
-            }
         case CRISV10_QIMM_BCC_R1:
         case CRISV10_QIMM_BCC_R2:
         case CRISV10_QIMM_BCC_R3: