lavc/flacdsp: change lpc_encoder function pointer prototype

This should help to clarify the API.
Reviewed-by: Christophe Gisquet <christophe.gisquet@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/flacdsp.h

@@ -28,7 +28,7 @@ typedef struct FLACDSPContext {
     void (*lpc)(int32_t *samples, const int coeffs[32], int order,
                 int qlevel, int len);
     void (*lpc_encode)(int32_t *res, const int32_t *smp, int len, int order,
-                       const int32_t *coefs, int shift);
+                       const int32_t coefs[32], int shift);
 } FLACDSPContext;
 
 void ff_flacdsp_init(FLACDSPContext *c, enum AVSampleFormat fmt, int bps);