Add SMI driver

Signed-off-by: Luke Wren <wren6991@gmail.com>

MISC: bcm2835: smi: use clock manager and fix reload issues

Use clock manager instead of self-made clockmanager.

Also fix some error paths that showd up during development
(especially missing release of dma resources on rmmod)

Signed-off-by: Martin Sperl <kernel@martin.sperl.org>

bcm2835_smi: re-add dereference to fix DMA transfers