fix unused parameter warning in {skge, sky2}_dump_regs()

This fixes:
  external/ethtool/marvell.c:262:44: error: unused parameter 'info' [-Werror,-Wunused-parameter]
  int skge_dump_regs(struct ethtool_drvinfo *info, struct ethtool_regs *regs)

  external/ethtool/marvell.c:382:44: error: unused parameter 'info' [-Werror,-Wunused-parameter]
  int sky2_dump_regs(struct ethtool_drvinfo *info, struct ethtool_regs *regs)

Signed-off-by: Maciej Żenczykowski <maze@google.com>
Change-Id: Ic60f9596ac59f15d44ebb80f9438c4978f13b48c
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/marvell.c b/marvell.c
index 27785be..9e5440d 100644
--- a/marvell.c
+++ b/marvell.c
@@ -259,7 +259,8 @@
 	printf("General Purpose  I/O             0x%08X\n", *(u32 *) (r + 0x15c));
 }
 
-int skge_dump_regs(struct ethtool_drvinfo *info, struct ethtool_regs *regs)
+int skge_dump_regs(struct ethtool_drvinfo *info maybe_unused,
+		   struct ethtool_regs *regs)
 {
 	const u32 *r = (const u32 *) regs->data;
 	int dual = !(regs->data[0x11a] & 1);
@@ -379,7 +380,8 @@
 	}
 }
 
-int sky2_dump_regs(struct ethtool_drvinfo *info, struct ethtool_regs *regs)
+int sky2_dump_regs(struct ethtool_drvinfo *info maybe_unused,
+		   struct ethtool_regs *regs)
 {
 	const u16 *r16 = (const u16 *) regs->data;
 	const u32 *r32 = (const u32 *) regs->data;