nvme: Add a break to make error injection more efficient

Change-Id: I3bddbb1caf11e17b2ecfa446adcc221b3aed595b
Signed-off-by: Ziye Yang <ziye.yang@intel.com>
Reviewed-on: https://review.gerrithub.io/416662
Tested-by: SPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: Changpeng Liu <changpeng.liu@intel.com>
Reviewed-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Reviewed-by: Daniel Verkamp <daniel.verkamp@intel.com>

lib/nvme/nvme_internal.h

@@ -765,6 +765,7 @@ nvme_complete_request(struct nvme_request *req, struct spdk_nvme_cpl *cpl)
 
 				cpl = &err_cpl;
 				cmd->err_count--;
+				break;
 			}
 		}
 	}