[media] media: Kconfig: add dependency of HAS_DMA

The build of m32r allmodconfig fails with the error:
drivers/media/v4l2-core/videobuf2-dma-contig.c:484:2:
	error: implicit declaration of function 'dma_get_cache_alignment'

The build of videobuf2-dma-contig.c depends on HAS_DMA and it is
correctly mentioned in the Kconfig but the symbol VIDEO_STI_BDISP also
selects VIDEOBUF2_DMA_CONTIG, so it is trying to compile
videobuf2-dma-contig.c even though HAS_DMA is not defined.

Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>