Add the required SC register configurations which lets us perform linear scaling
for the supported range of horizontal and vertical scaling ratios.

The horizontal scaler performs polyphase scaling using it's 8 tap 32 phase
filter, decimation is performed when downscaling passes beyond 2x or 4x.

The vertical scaler performs polyphase scaling using it's 5 tap 32 phase filter,
it switches to a simpler form of scaling using the running average filter when
the downscale ratio is more than 4x.

Many of the SC features like peaking, trimming and non-linear scaling aren't
implemented for now. Only the minimal register fields required for basic scaling
operation are configured.

The function to configure SC registers takes the sc_data handle, the source and
destination widths and heights, and the scaler address data block offsets for
the current context so that they can be configured.
Signed-off-by: Archit Taneja <archit@ti.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>