Do not read uninitialized buffer, no matter if it will be multiplied by

zero later. This should fix some valgrind warnings and hopefully FATE
ra144 test on ARM.

Originally committed as revision 17677 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/ra144.c

@@ -138,8 +138,13 @@ static void add_wav(int16_t *dest, int n, int skip_first, int *m,
     for (i=!skip_first; i<3; i++)
         v[i] = (gain_val_tab[n][i] * m[i]) >> gain_exp_tab[n];
 
+    if (v[0]) {
     for (i=0; i < BLOCKSIZE; i++)
         dest[i] = (s1[i]*v[0] + s2[i]*v[1] + s3[i]*v[2]) >> 12;
+    } else {
+        for (i=0; i < BLOCKSIZE; i++)
+            dest[i] = (s2[i]*v[1] + s3[i]*v[2]) >> 12;
+    }
 }
 
 static unsigned int rescale_rms(unsigned int rms, unsigned int energy)