camera: Add options to better control video preview size

 * usePreferredPreviewSizeForEffects is needed to fix camcorder effect on
   some MSM8660 devices.
 * Add ignorePreferredPreviewSizeForVideo to use the best size reported
   by the driver instead of the preferred-preview-size-for-video value,
   which may report something really awful.

Change-Id: I216502fe032a89f69e1aea11bc50c51634d40991