ARM: EXYNOS: Decouple ARCH_EXYNOS from PLAT_S5P

After removing support for ATAGS based boot on Exynos, there is not much
that can be shared between Exynos and other S5P platforms. This patch
makes Exynos a standalone Samsung platform, not using PLAT_S5P.

Signed-off-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
diff --git a/arch/arm/Makefile b/arch/arm/Makefile
index 1ba358b..60133fb 100644
--- a/arch/arm/Makefile
+++ b/arch/arm/Makefile
@@ -197,6 +197,7 @@
 
 # Platform directory name.  This list is sorted alphanumerically
 # by CONFIG_* macro name.
+plat-$(CONFIG_ARCH_EXYNOS)	+= samsung
 plat-$(CONFIG_ARCH_OMAP)	+= omap
 plat-$(CONFIG_ARCH_S3C64XX)	+= samsung
 plat-$(CONFIG_PLAT_IOP)		+= iop