10886 smatch debug macro cleanup in usr/src/uts

@@ -32,10 +32,14 @@
  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
  * THE POSSIBILITY OF SUCH DAMAGES.
  */
 
 /*
+ * Copyright 2019 Joyent, Inc.
+ */
+
+/*
  * Driver for the Marvell 88W8363 Wireless LAN controller.
  */
 #include <sys/stat.h>
 #include <sys/dlpi.h>
 #include <inet/common.h>

@@ -126,11 +130,11 @@
 
 #ifdef DEBUG
 #define MWL_DBG \
         mwl_debug
 #else
-#define MWL_DBG
+#define MWL_DBG(...) (void)(0)
 #endif
 
 /*
  * PIO access attributes for registers
  */