Fixed invalid assertion in end_irob; since we do retransmission, we should check whether the IROB exists first.
Fixed invalid assertion in end_irob; since we do retransmission, we should check whether the IROB exists first.

brettdh/libcmm,brettdh/libcmm,brettdh/libcmm,brettdh/libcmm,brettdh/libcmm