Make sure all the bits are written to output in fax data decoder.

This fixes decoding TIFF images with fax compression and width being not
multiple of eight (and issue 1429).

Originally committed as revision 20072 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/faxcompr.c

@@ -253,6 +253,7 @@ static void put_line(uint8_t *dst, int size, int width, const int *runs)
         if(run)
             put_sbits(&pb, run, mode);
     }
+    flush_put_bits(&pb);
 }
 
 static int find_group3_syncmarker(GetBitContext *gb, int srcsize)