mm-video-v4l2: decouple B-frame disablement from narrow search range

Remove display panel resolution dependency to enable narrow search range.
Disabling B-Frames not achieving any power optimization, so honor client
preferences to set intra period.

CRs-Fixed: 715276
Change-Id: I5a2218ac20f5c48802a176177a710133d4d8c53f