ublksrv_tgt: convert syslog(LOG_ERR) into ublk_err()

Signed-off-by: Ming Lei <[email protected]>
diff --git a/include/ublksrv_tgt.h b/include/ublksrv_tgt.h
index e65ae6d..95ad578 100644
--- a/include/ublksrv_tgt.h
+++ b/include/ublksrv_tgt.h
@@ -23,7 +23,7 @@
 
 #define ublk_assert(x)  do { \
 	if (!(x)) {	\
-		syslog(LOG_ERR, "%s %d: assert!\n", __func__, __LINE__); \
+		ublk_err("%s %d: assert!\n", __func__, __LINE__); \
 		assert(x);	\
 	}	\
 } while (0)