mm-vidc-v4l2: vidc: venc: Set proper color format if gralloc source

This changes sets color format to encoder as per gralloc handle.
It also calls REQBUFS before calling QBUF, else provided buffer
size will be less than setup size for plane and qbuf call fails.

Change-Id: Id2422c1e0ca2007933c40ce784fa7b59cf436e19
1 file changed