demux: mp4: add support for computer graphics meta atom

see bartjones.mov
http://streams.videolan.org/samples/mov/unrecognized/

modules/demux/mp4/libmp4.c

@@ -3338,6 +3338,7 @@ static const struct
     { ATOM_skip,    MP4_ReadBoxSkip,          MP4_FreeBox_Common },
     { ATOM_free,    MP4_ReadBoxSkip,          MP4_FreeBox_Common },
     { ATOM_wide,    MP4_ReadBoxSkip,          MP4_FreeBox_Common },
+    { ATOM_binm,    MP4_ReadBoxSkip,          MP4_FreeBox_Common },
 
     /* Subtitles */
     { ATOM_tx3g,    MP4_ReadBox_sample_tx3g,      MP4_FreeBox_Common },

modules/demux/mp4/libmp4.h

@@ -43,6 +43,7 @@
 #define ATOM_free VLC_FOURCC( 'f', 'r', 'e', 'e' )
 #define ATOM_udta VLC_FOURCC( 'u', 'd', 't', 'a' )
 #define ATOM_wide VLC_FOURCC( 'w', 'i', 'd', 'e' )
+#define ATOM_binm VLC_FOURCC( 0x82, 0x82, 0x7f, 0x7d ) /* binary Computer Graphics Metafile */
 
 #define ATOM_data VLC_FOURCC( 'd', 'a', 't', 'a' )