[media] cx23885-video: fix two warnings

drivers/media/pci/cx23885/cx23885-video.c:420:5: warning: no previous prototype for 'cx23885_flatiron_write' [-Wmissing-prototypes]
 int cx23885_flatiron_write(struct cx23885_dev *dev, u8 reg, u8 data)
     ^
drivers/media/pci/cx23885/cx23885-video.c:431:4: warning: no previous prototype for 'cx23885_flatiron_read' [-Wmissing-prototypes]
 u8 cx23885_flatiron_read(struct cx23885_dev *dev, u8 reg)
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

drivers/media/pci/cx23885/cx23885-video.c

@@ -32,6 +32,7 @@
 #include <asm/div64.h>
 
 #include "cx23885.h"
+#include "cx23885-video.h"
 #include <media/v4l2-common.h>
 #include <media/v4l2-ioctl.h>
 #include "cx23885-ioctl.h"