powerpc: keymile: Add a check for the PIGGY debug board

Check the presence of the PIGGY on the keymile boards mgcoge,
mgsuvd and kmeter1. If the PIGGY is not present, dont register
this Ethernet device.

Signed-off-by: Heiko Schocher <hs@denx.de>
Acked-by: Ben Warren <biggerbadderben@gmail.com>
diff --git a/board/keymile/kmeter1/Makefile b/board/keymile/kmeter1/Makefile
index 88b79f3..12a1518 100644
--- a/board/keymile/kmeter1/Makefile
+++ b/board/keymile/kmeter1/Makefile
@@ -22,12 +22,14 @@
 #
 
 include $(TOPDIR)/config.mk
+ifneq ($(OBJTREE),$(SRCTREE))
+$(shell mkdir -p $(obj)../common)
+endif
 
 LIB	= $(obj)lib$(BOARD).a
 
-COBJS-y += $(BOARD).o
+COBJS	+= $(BOARD).o ../common/common.o
 
-COBJS	:= $(COBJS-y)
 SRCS	:= $(SOBJS:.o=.S) $(COBJS:.o=.c)
 OBJS	:= $(addprefix $(obj),$(COBJS))
 SOBJS	:= $(addprefix $(obj),$(SOBJS))