ipu: moved display mem block allocation into show_frame() ; cleanup

Signed-off-by: Carlos Rafael Giani <dv@pseudoterminal.org>
ipu: begun adding videotransform element

Signed-off-by: Carlos Rafael Giani <dv@pseudoterminal.org>
ipu: sink: added alternative buffer pool which allocates buffers on heap

sinks should always propose buffers upstream, since for example
videotestsrc will produce buffers without video metadata otherwise

Signed-off-by: Carlos Rafael Giani <dv@pseudoterminal.org>
ipu: videotransform: output with padding is now supported

task information has to be set in transform_frame() now, since the stride
is not present in set_info()'s out_info structure

Signed-off-by: Carlos Rafael Giani <dv@pseudoterminal.org>
ipu: buffer pool: added horizontal 8-pixel alignment

IPU cannot work with framebuffers that aren't 8-pixel aligned

Signed-off-by: Carlos Rafael Giani <dv@pseudoterminal.org>
ipu: sink: show_frame() uses video metadata again

video metadata contains information the caps don't, like custom stride
values

Signed-off-by: Carlos Rafael Giani <dv@pseudoterminal.org>