Fix postproc build, thanks to Pavlov Konstantin <thresh@cpms.ru>

Originally committed as revision 6534 to svn://svn.ffmpeg.org/ffmpeg/trunk

libpostproc/Makefile

@@ -4,6 +4,8 @@ include ../config.mak
 # Overload incdir, postproc include files go in a different directory.
 incdir=$(prefix)/include/postproc
 
+EXTRALIBS := -L../libavutil -lavutil$(BUILDSUF) $(EXTRALIBS)
+
 NAME=postproc
 ifeq ($(BUILD_SHARED),yes)
 LIBVERSION=$(SPPVERSION)