This patch changes the most part of mach-bcm2835 to mach-bcm283x. This
prepares to add RPi2 support which is a bcm2836. This patch changes the
Kconfig entry namens to BCM283X for drivers only. These drivers should
working the same in bcm2836.

While updating defconfig I added LED support/trigger option.

Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>