V4L2: parse v4l2://:standard=XXX like --v4l2-standard=XXX...

...and fix buffer read overflow.

modules/access/v4l2.c

@@ -792,7 +792,7 @@ static void ParseMRL( demux_sys_t *p_sys, char *psz_path, vlc_object_t *p_obj )
                 }
 
                 if( i == ARRAY_SIZE(psz_standards_list_text) )
-                    p_sys->i_selected_standard_id = i_standards_list[strtol( psz_parser, &psz_parser, 0 )];
+                    p_sys->i_selected_standard_id = strtol( psz_parser, &psz_parser, 0 );
             }
             else if( !strncmp( psz_parser, "chroma=", strlen( "chroma=" ) ) )
             {