msm: wfd: paddr cannot be null

Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
msm: wfd:Wait for one more vsync cycle, if VSG running out of
 input frames

If VSG running out of input frames, it will re-encode previous frames.
With this change, instead of encoding pervious frame VSG will push timer to
half of capturing frame rate. If it find new frame, it will be encoded
Otherwise will re-encode previous frame.

Signed-off-by: Srinu Gorle <sgorle@codeaurora.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>