nios2: Offer ft_board_setup() capability and call fdt_fixup_ethernet().

The main motivation is, to have the local-mac-address property of the
ethernet peripherals fixed/synced with U-Boot's environment settings.

Signed-off-by: Joachim Foerster <joachim.foerster@missinglinkelectronics.com>
Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
diff --git a/arch/nios2/cpu/Makefile b/arch/nios2/cpu/Makefile
index aa41160..402fd74 100644
--- a/arch/nios2/cpu/Makefile
+++ b/arch/nios2/cpu/Makefile
@@ -28,6 +28,7 @@
 START	= start.o
 SOBJS	= exceptions.o
 COBJS	= cpu.o interrupts.o sysid.o traps.o epcs.o
+COBJS	+= fdt.o
 
 SRCS	:= $(START:.o=.S) $(SOBJS:.o=.S) $(COBJS:.o=.c)
 OBJS	:= $(addprefix $(obj),$(SOBJS) $(COBJS))