g729dec: Fix warnings:

libavcodec/g729dec.c: In function ‘decode_frame’:
libavcodec/g729dec.c:662: warning: passing argument 3 of ‘ff_g729_postfilter’ from incompatible pointer type
libavcodec/g729postfilter.h:96: note: expected ‘int16_t *’ but argument is of type ‘int *’
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/g729postfilter.c

@@ -511,7 +511,7 @@ static int16_t apply_tilt_comp(int16_t* out, int16_t* res_pst, int refl_coeff,
     return tmp;
 }
 
-void ff_g729_postfilter(DSPContext *dsp, int16_t* ht_prev_data, int16_t* voicing,
+void ff_g729_postfilter(DSPContext *dsp, int16_t* ht_prev_data, int* voicing,
                      const int16_t *lp_filter_coeffs, int pitch_delay_int,
                      int16_t* residual, int16_t* res_filter_data,
                      int16_t* pos_filter_data, int16_t *speech, int subframe_size)

libavcodec/g729postfilter.h

@@ -93,7 +93,7 @@
  *   Short-term postfilter (4.2.2).
  *   Tilt-compensation (4.2.3)
  */
-void ff_g729_postfilter(DSPContext *dsp, int16_t* ht_prev_data, int16_t* voicing,
+void ff_g729_postfilter(DSPContext *dsp, int16_t* ht_prev_data, int* voicing,
                      const int16_t *lp_filter_coeffs, int pitch_delay_int,
                      int16_t* residual, int16_t* res_filter_data,
                      int16_t* pos_filter_data, int16_t *speech,