V4L/DVB (3914): Vivi build fix

drivers/media/video/vivi.c: In function `vivi_map_sg':
drivers/media/video/vivi.c:799: error: `DMA_NONE' undeclared (first use in this function)
drivers/media/video/vivi.c:799: error: (Each undeclared identifier is reported only once
drivers/media/video/vivi.c:799: error: for each function it appears in.)

Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Mauro Carvalho Chehab <[e-mail]>

drivers/media/video/vivi.c

···
 #include <linux/random.h>
 #include <linux/version.h>
 #include <linux/videodev2.h>
+#include <linux/dma-mapping.h>
 #ifdef CONFIG_VIDEO_V4L1_COMPAT
 /* Include V4L1 specific functions. Should be removed soon */
 #include <linux/videodev.h>