video: Fix kernel-doc warnings in of_display_timing + of_videomode

Fix kernel-doc warnings reported when using W=1.

v3:
  - Do not replace '-' with ':' (Thomas)

v2:
  - Improve subject (Lee)
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: linux-fbdev@vger.kernel.org
Link: https://patchwork.freedesktop.org/patch/msgid/20201128224114.1033617-2-sam@ravnborg.org

drivers/video/of_display_timing.c

@@ -52,6 +52,7 @@ static int parse_timing_property(const struct device_node *np, const char *name,
 /**
  * of_parse_display_timing - parse display_timing entry from device_node
  * @np: device_node with the properties
+ * @dt: display_timing that contains the result. I may be partially written in case of errors
  **/
 static int of_parse_display_timing(const struct device_node *np,
 		struct display_timing *dt)

drivers/video/of_videomode.c

@@ -14,9 +14,9 @@
 
 /**
  * of_get_videomode - get the videomode #<index> from devicetree
- * @np - devicenode with the display_timings
- * @vm - set to return value
- * @index - index into list of display_timings
+ * @np: devicenode with the display_timings
+ * @vm: set to return value
+ * @index: index into list of display_timings
  *	    (Set this to OF_USE_NATIVE_MODE to use whatever mode is
  *	     specified as native mode in the DT.)
  *