nvmet: use helper to remove the duplicate code

Use the helper nvmet_report_invalid_opcode() to report invalid opcode
so we can remove the duplicate code.
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

drivers/nvme/target/admin-cmd.c

@@ -975,10 +975,7 @@ u16 nvmet_parse_admin_cmd(struct nvmet_req *req)
 	case nvme_admin_keep_alive:
 		req->execute = nvmet_execute_keep_alive;
 		return 0;
+	default:
+		return nvmet_report_invalid_opcode(req);
 	}
-
-	pr_debug("unhandled cmd %d on qid %d\n", cmd->common.opcode,
-	       req->sq->qid);
-	req->error_loc = offsetof(struct nvme_common_command, opcode);
-	return NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
 }