avr32: convert makefiles to Kbuild style

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Cc: Andreas Bießmann <andreas.devel@googlemail.com>
diff --git a/board/earthlcd/favr-32-ezkit/Makefile b/board/earthlcd/favr-32-ezkit/Makefile
index 0b3ebe3..f712ab9 100644
--- a/board/earthlcd/favr-32-ezkit/Makefile
+++ b/board/earthlcd/favr-32-ezkit/Makefile
@@ -6,23 +6,4 @@
 #
 # SPDX-License-Identifier:	GPL-2.0+
 
-include $(TOPDIR)/config.mk
-
-LIB	:= $(obj)lib$(BOARD).o
-
-COBJS	:= $(BOARD).o flash.o
-
-SRCS	:= $(SOBJS:.o=.S) $(COBJS:.o=.c)
-OBJS	:= $(addprefix $(obj),$(SOBJS) $(COBJS))
-
-$(LIB): $(obj).depend $(OBJS)
-	$(call cmd_link_o_target, $(OBJS))
-
-#########################################################################
-
-# defines $(obj).depend target
-include $(SRCTREE)/rules.mk
-
-sinclude $(obj).depend
-
-#########################################################################
+obj-y	:= favr-32-ezkit.o flash.o