msm: vidc: Add NV21 input format type

This change adds the NV21 format in different input
formats for YUV data.

Change-Id: Ide693295ae0cbc6724edfb8cbc0fba30009394b4
CRs-fixed: 448511
Signed-off-by: Deepak Verma <dverma@codeaurora.org>