m32r: Rearrange platform-dependent codes

Rearrange platform-dependent codes from arch/m32r/kernel/*.c
to arch/m32r/platforms/{platform}/.

Signed-off-by: Hirokazu Takata <takata@linux-m32r.org>
diff --git a/arch/m32r/Makefile b/arch/m32r/Makefile
index cdf63b2..60e12f3 100644
--- a/arch/m32r/Makefile
+++ b/arch/m32r/Makefile
@@ -36,7 +36,8 @@
 libs-y	+= arch/m32r/lib/ $(LIBGCC)
 core-y	+= arch/m32r/kernel/	\
 	   arch/m32r/mm/	\
-	   arch/m32r/boot/
+	   arch/m32r/boot/	\
+	   arch/m32r/platforms/
 
 drivers-$(CONFIG_OPROFILE)	+= arch/m32r/oprofile/