videobuf-dvb were still using a function that were videobuf-dma-sg
dependent. This patch creates a generic handler for this function. This
way, videobuf-dvb can now work with all videobuf implementations.
Signed-off-by: NMauro Carvalho Chehab <mchehab@infradead.org>

Signed-off-by: NBrandon Philips <bphilips@suse.de>
Signed-off-by: NMauro Carvalho Chehab <mchehab@infradead.org>

Signed-off-by: NMauro Carvalho Chehab <mchehab@infradead.org>
http://thread.gmane.org/gmane.comp.video.video4linux/34978/focus=34981Reviewed-by: NRicardo Cerqueira <v4l@cerqueira.org>

Adds a newer videobuf-vmalloc module. This module uses the same
videobuf controls, but implements memory allocation based on vmalloc
methods.

With this method, an USB driver can use video-buf, without needing to
request memory from the DMA-safe area.
Signed-off-by: NMauro Carvalho Chehab <mchehab@infradead.org>