[media] OMAP_VOUT: Create separate file for VRFB related API's

Introduce omap_vout_vrfb.c and omap_vout_vrfb.h, for all VRFB related API's,
making OMAP_VOUT driver independent from VRFB. This is required for OMAP4 DSS,
since OMAP4 doesn't have VRFB block.

Added new enum vout_rotation_type and "rotation_type" member to omapvideo_info,
this is initialized based on the arch type in omap_vout_probe. The rotation_type
var is now used to choose between vrfb and non-vrfb calls.

Signed-off-by: Archit Taneja <archit@ti.com>
Signed-off-by: Vaibhav Hiremath <hvaibhav@ti.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>