keep in sync with dsputil, makes --disable-decoder=vorbis build

git-svn-id: file:///var/local/repositories/ffmpeg/trunk@5979 9553f0bf-9b14-0410-a0b8-cfaf0461ba5b

libavcodec/ppc/dsputil_altivec.c

@@ -1854,5 +1854,7 @@ void dsputil_init_altivec(DSPContext* c, AVCodecContext *avctx)
 
     c->hadamard8_diff[0] = hadamard8_diff16_altivec;
     c->hadamard8_diff[1] = hadamard8_diff8x8_altivec;
+#ifdef CONFIG_VORBIS_DECODER
     c->vorbis_inverse_coupling = vorbis_inverse_coupling_altivec;
+#endif
 }