Remove explicit filename from Doxygen @file commands.

Passing an explicit filename to this command is only necessary if the
documentation in the @file block refers to a file different from the
one the block resides in.

Originally committed as revision 22921 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/mpc7.c

@@ -20,7 +20,7 @@
  */
 
 /**
- * @file libavcodec/mpc7.c Musepack SV7 decoder
+ * @file
  * MPEG Audio Layer 1/2 -like codec with frames of 1152 samples
  * divided into 32 subbands.
  */