msm: vidc: Change default width & height

Change default width & height for 1080p to
QVGA. Having 1080p as default, creates issue in
concurrent sessions for low end targets where
max capability is 1080p.

CRs-Fixed: 2602438
Change-Id: I0ca9d8633af1882abd5dbfd113c7dd55cd399f0a
Signed-off-by: Manikanta Kanamarlapudi <kmanikan@codeaurora.org>