ARM: convert makefiles to Kbuild style

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
diff --git a/arch/arm/cpu/tegra20-common/Makefile b/arch/arm/cpu/tegra20-common/Makefile
index 175387f..32ddbda 100644
--- a/arch/arm/cpu/tegra20-common/Makefile
+++ b/arch/arm/cpu/tegra20-common/Makefile
@@ -7,32 +7,11 @@
 # SPDX-License-Identifier:	GPL-2.0+
 #
 
-include $(TOPDIR)/config.mk
-
 # The AVP is ARMv4T architecture so we must use special compiler
 # flags for any startup files it might use.
 CFLAGS_arch/arm/cpu/tegra20-common/warmboot_avp.o += -march=armv4t
 
-LIB	= $(obj)lib$(SOC)-common.o
-
-COBJS-y	+= clock.o funcmux.o pinmux.o
-COBJS-$(CONFIG_TEGRA_LP0) += warmboot.o crypto.o warmboot_avp.o
-COBJS-$(CONFIG_TEGRA_CLOCK_SCALING) += emc.o
-COBJS-$(CONFIG_TEGRA_PMU) += pmu.o
-
-SRCS	:= $(SOBJS:.o=.S) $(COBJS-y:.o=.c)
-OBJS	:= $(addprefix $(obj),$(SOBJS) $(COBJS-y))
-
-all:	$(obj).depend $(LIB)
-
-$(LIB):	$(OBJS)
-	$(call cmd_link_o_target, $(OBJS))
-
-#########################################################################
-
-# defines $(obj).depend target
-include $(SRCTREE)/rules.mk
-
-sinclude $(obj).depend
-
-#########################################################################
+obj-y	+= clock.o funcmux.o pinmux.o
+obj-$(CONFIG_TEGRA_LP0) += warmboot.o crypto.o warmboot_avp.o
+obj-$(CONFIG_TEGRA_CLOCK_SCALING) += emc.o
+obj-$(CONFIG_TEGRA_PMU) += pmu.o