ARM: shmobile: marzen: Switch to DT_MACHINE_START

Convert the marzen board to use DT_MACHINE_START. With this in
place all mach-shmobile boards use DT_MACHINE_START. Also, this
makes it possible for the r8a7779 SMP code to use DT for CPUs.

Signed-off-by: Magnus Damm <damm@opensource.se>
[horms+renesas@verge.net.au: Select USE_OF in Kconfig]
[horms+renesas@verge.net.au: Provide dt_compat in DT_MACHINE_START]
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
diff --git a/arch/arm/mach-shmobile/Kconfig b/arch/arm/mach-shmobile/Kconfig
index 9e07985..16c3072 100644
--- a/arch/arm/mach-shmobile/Kconfig
+++ b/arch/arm/mach-shmobile/Kconfig
@@ -156,6 +156,7 @@
 	depends on ARCH_R8A7779
 	select ARCH_REQUIRE_GPIOLIB
 	select REGULATOR_FIXED_VOLTAGE if REGULATOR
+	select USE_OF
 
 config MACH_MARZEN_REFERENCE
 	bool "MARZEN board - Reference Device Tree Implementation"