OMXCodec: Support older QCOM video decoders

Pre-JB qcom decoders calculated buffer dimensions based on stride
and slice instead of the video frame dimensions. If for some reason
a device uses older (ICS, possibly HC) OMX libraries, enable this
behavior with QCOM_ICS_DECODERS

Change-Id: Id7f48bf79e3bfd5bcf692eb8165edde2b426a351