ARM: bcm2835_defconfig: Enable RPi power domain driver

After enabling the Raspberry Pi firmware driver which allow us to handle
power domains for USB or graphics.
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Eric Anholt <eric@anholt.net>

arch/arm/configs/bcm2835_defconfig

@@ -106,6 +106,7 @@ CONFIG_STAGING=y
 CONFIG_MAILBOX=y
 CONFIG_BCM2835_MBOX=y
 # CONFIG_IOMMU_SUPPORT is not set
+CONFIG_RASPBERRYPI_POWER=y
 CONFIG_PWM=y
 CONFIG_PWM_BCM2835=y
 CONFIG_RASPBERRYPI_FIRMWARE=y