[media] add mux and video interface bridge entity functions

Add two new media entity function definitions for video multiplexers
and video interface bridges.

- renamed MEDIA_ENT_F_MUX to MEDIA_ENT_F_VID_MUX

Signed-off-by: Philipp Zabel <[e-mail]>
Signed-off-by: Steve Longerbeam <[e-mail]>
Acked-by: Sakari Ailus <[e-mail]>
Signed-off-by: Hans Verkuil <[e-mail]>
Signed-off-by: Mauro Carvalho Chehab <[e-mail]>

Documentation/media/uapi/mediactl/media-types.rst

···
 	  received on its sink pad and outputs the statistics data on
 	  its source pad.
 
+    -  ..  row 29
+
+       ..  _MEDIA-ENT-F-VID-MUX:
+
+       -  ``MEDIA_ENT_F_VID_MUX``
+
+       - Video multiplexer. An entity capable of multiplexing must have at
+         least two sink pads and one source pad, and must pass the video
+         frame(s) received from the active sink pad to the source pad.
+
+    -  ..  row 30
+
+       ..  _MEDIA-ENT-F-VID-IF-BRIDGE:
+
+       -  ``MEDIA_ENT_F_VID_IF_BRIDGE``
+
+       - Video interface bridge. A video interface bridge entity must have at
+         least one sink pad and at least one source pad. It receives video
+         frames on its sink pad from an input video bus of one type (HDMI, eDP,
+         MIPI CSI-2, ...), and outputs them on its source pad to an output
+         video bus of another type (eDP, MIPI CSI-2, parallel, ...).
 
 ..  tabularcolumns:: |p{5.5cm}|p{12.0cm}|
 

include/uapi/linux/media.h

···
 #define MEDIA_ENT_F_PROC_VIDEO_STATISTICS	(MEDIA_ENT_F_BASE + 0x4006)
 
 /*
+ * Switch and bridge entitites
+ */
+#define MEDIA_ENT_F_VID_MUX			(MEDIA_ENT_F_BASE + 0x5001)
+#define MEDIA_ENT_F_VID_IF_BRIDGE		(MEDIA_ENT_F_BASE + 0x5002)
+
+/*
  * Connectors
  */
 /* It is a responsibility of the entity drivers to add connectors and links */