fix unused parameter warning in smsc911x_dump_regs()

This fixes:
  external/ethtool/smsc911x.c:5:48: error: unused parameter 'info' [-Werror,-Wunused-parameter]
  int smsc911x_dump_regs(struct ethtool_drvinfo *info, struct ethtool_regs *regs)

Signed-off-by: Maciej Żenczykowski <maze@google.com>
Change-Id: I419e8e365481020241303033fcdfaf31aaf4e178
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/smsc911x.c b/smsc911x.c
index c55b97b..bafee21 100644
--- a/smsc911x.c
+++ b/smsc911x.c
@@ -2,7 +2,8 @@
 #include <string.h>
 #include "internal.h"
 
-int smsc911x_dump_regs(struct ethtool_drvinfo *info, struct ethtool_regs *regs)
+int smsc911x_dump_regs(struct ethtool_drvinfo *info maybe_unused,
+		       struct ethtool_regs *regs)
 {
 	unsigned int *smsc_reg = (unsigned int *)regs->data;