fixup! bcm2708 framebuffer driver

Make CONFIG_FB_BCM2708 select CONFIG_FB_DEVICE, to avoid potential build
problems.

See: #6059

Signed-off-by: Phil Elwell <phil@raspberrypi.com>

drivers/video/fbdev/Kconfig

@@ -64,6 +64,7 @@ config FB_MACMODES
 config FB_BCM2708
 	tristate "BCM2708 framebuffer support"
 	depends on FB && RASPBERRYPI_FIRMWARE
+	select FB_DEVICE
 	select FB_CFB_FILLRECT
 	select FB_CFB_COPYAREA
 	select FB_CFB_IMAGEBLIT