[media] coda: move BIT specific functions into separate file

This patch moves the BIT processor specific coda_context_ops, the firmware
upload and other related functions from coda-common.c into coda-bit.c.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Kamil Debski <k.debski@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>