media: v4l2: Documentation of HEVC compressed format

Add V4L2 definition for HEVC compressed format which is also
known as H.265.
Signed-off-by: NSmitha T Murthy <smitha.t@samsung.com>
Reviewed-by: NAndrzej Hajda <a.hajda@samsung.com>
Reviewed-by: NStanimir Varbanov <stanimir.varbanov@linaro.org>
Acked-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NSylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

Documentation/media/uapi/v4l/pixfmt-compressed.rst

@@ -90,3 +90,8 @@ Compressed Formats
       - ``V4L2_PIX_FMT_VP9``
       - 'VP90'
       - VP9 video elementary stream.
+    * .. _V4L2-PIX-FMT-HEVC:
+
+      - ``V4L2_PIX_FMT_HEVC``
+      - 'HEVC'
+      - HEVC/H.265 video elementary stream.