ARM: bcm283x: use OF_CONTROL for bcm283x

This patch removes use of U_BOOT_DEVICE in board/raspberrypi/rpi/rpi.c,
enables OF_CONTROL in the config and adjusts the rpi_*defconfig configs.

Signed-off-by: Fabian Vogt <fvogt@suse.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 220022b..fcbf1d8 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -321,6 +321,7 @@
 	select DM
 	select DM_SERIAL
 	select DM_GPIO
+	select OF_CONTROL
 
 config TARGET_VEXPRESS_CA15_TC2
 	bool "Support vexpress_ca15_tc2"