Add missing static qualifier from function declaration. Patch by Kenan

Gillet.

Originally committed as revision 18331 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/qcelpdec.c

@@ -586,7 +586,7 @@ static void apply_pitch_filters(QCELPContext *q, float *cdn_vector)
  *
  * TIA/EIA/IS-733 2.4.3.3.5
  */
-void lspf2lpc(const float *lspf, float *lpc)
+static void lspf2lpc(const float *lspf, float *lpc)
 {
     double lsf[10];
     double bandwith_expansion_coeff = QCELP_BANDWITH_EXPANSION_COEFF;