V4L/DVB (6921): include/media/v4l2-i2c-drv.h must #include <media/v4l2-common.h>

Fix the following compiler error:

v4l2-i2c-drv.h:72: error: implicit declaration of function 'v4l2_i2c_attach'

Also, prevent multiple inclusions of v4l2-i2c-drv.h

Signed-off-by: Michael Krufky <mkrufky@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
diff --git a/include/media/v4l2-i2c-drv.h b/include/media/v4l2-i2c-drv.h
index d758b76..9e4bab2 100644
--- a/include/media/v4l2-i2c-drv.h
+++ b/include/media/v4l2-i2c-drv.h
@@ -21,6 +21,11 @@
  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+#ifndef __V4L2_I2C_DRV_H__
+#define __V4L2_I2C_DRV_H__
+
+#include <media/v4l2-common.h>
+
 struct v4l2_i2c_driver_data {
 	const char * const name;
 	int driverid;
@@ -59,3 +64,5 @@
 
 module_init(v4l2_i2c_drv_init);
 module_exit(v4l2_i2c_drv_cleanup);
+
+#endif /* __V4L2_I2C_DRV_H__ */