V4L2: Add support for setting H264_I_PERIOD

Adds support for the parameter V4L2_CID_MPEG_VIDEO_H264_I_PERIOD
to set the frequency with which I frames are produced.

Signed-off-by: Dave Stevenson <dsteve@broadcom.com>
V4L2: Enable GPU function for removing padding from images.

GPU can now support arbitrary strides, although may require
additional processing to achieve it. Enable this feature
so that the images delivered are the size requested.

Signed-off-by: Dave Stevenson <dsteve@broadcom.com>
V4L2: Add support for V4L2_PIX_FMT_BGR32

Signed-off-by: Dave Stevenson <dsteve@broadcom.com>
V4L2: Set the colourspace to avoid odd YUV-RGB conversions

Removes the amiguity from the conversion routines and stops
them dropping back to the SD vs HD choice of coeffs.

Signed-off-by: Dave Stevenson <dsteve@broadcom.com>
V4L2: Make video/still threshold a run-time param

Move the define for at what resolution the driver
switches from a video mode capture to a stills mode
capture to module parameters.

Signed-off-by: Dave Stevenson <dsteve@broadcom.com>
Merge pull request #598 from 6by9/rpi-3.12.y

V4L2 padding removal, and support for H264_I_PERIOD