[media] am437x: VIDEO_AM437X_VPFE should depend on HAS_DMA

If NO_DMA=y:

    warning: (VIDEO_AM437X_VPFE && VIDEO_DM365_VPFE && VIDEO_DT3155 && VIDEO_OMAP4) selects VIDEOBUF2_DMA_CONTIG which has unmet direct dependencies (MEDIA_SUPPORT && HAS_DMA)

    drivers/media/v4l2-core/videobuf2-dma-contig.c: In function ‘vb2_dc_mmap’:
    drivers/media/v4l2-core/videobuf2-dma-contig.c:207: error: implicit declaration of function ‘dma_mmap_coherent’
    drivers/media/v4l2-core/videobuf2-dma-contig.c: In function ‘vb2_dc_get_base_sgt’:
    drivers/media/v4l2-core/videobuf2-dma-contig.c:390: error: implicit declaration of function ‘dma_get_sgtable’

VIDEO_AM437X_VPFE selects VIDEOBUF2_DMA_CONTIG, which bypasses its
dependency on HAS_DMA.  Make VIDEO_AM437X_VPFE depend on HAS_DMA to fix
this.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Lad, Prabhakar <prabhakar.csengg@gmail.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

drivers/media/platform/am437x/Kconfig

 config VIDEO_AM437X_VPFE
 	tristate "TI AM437x VPFE video capture driver"
-	depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API
+	depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API && HAS_DMA
 	depends on SOC_AM43XX || COMPILE_TEST
 	select VIDEOBUF2_DMA_CONTIG
 	help