media: cec-ioc-dqevent.rst: document the new 5V events

Document the two new 5V events.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

Documentation/media/uapi/cec/cec-ioc-dqevent.rst

@@ -179,6 +179,24 @@ it is guaranteed that the state did change in between the two events.
 	capability set. When open() is called, the HPD pin can be read and
 	if the HPD is high, then an initial event will be generated for that
 	filehandle.
+    * .. _`CEC-EVENT-PIN-5V-LOW`:
+
+      - ``CEC_EVENT_PIN_5V_LOW``
+      - 6
+      - Generated if the 5V pin goes from a high voltage to a low voltage.
+	Only applies to adapters that have the ``CEC_CAP_MONITOR_PIN``
+	capability set. When open() is called, the 5V pin can be read and
+	if the 5V is low, then an initial event will be generated for that
+	filehandle.
+    * .. _`CEC-EVENT-PIN-5V-HIGH`:
+
+      - ``CEC_EVENT_PIN_5V_HIGH``
+      - 7
+      - Generated if the 5V pin goes from a low voltage to a high voltage.
+	Only applies to adapters that have the ``CEC_CAP_MONITOR_PIN``
+	capability set. When open() is called, the 5V pin can be read and
+	if the 5V is high, then an initial event will be generated for that
+	filehandle.
 
 
 .. tabularcolumns:: |p{6.0cm}|p{0.6cm}|p{10.9cm}|