aacenc: avoid double in quantize_bands.

I cannot see any point whatsoever to use
double here instead of float, the results
are likely identical in all cases..
Using float allows for much more
efficient use of SIMD.

Signed-off-by: Reimar Döffinger <Reimar.Doeffinger@gmx.de>

libavcodec/aacenc_utils.h

@@ -66,10 +66,9 @@ static inline void quantize_bands(int *out, const float *in, const float *scaled
                                   const float rounding)
 {
     int i;
-    double qc;
     for (i = 0; i < size; i++) {
-        qc = scaled[i] * Q34;
-        out[i] = (int)FFMIN(qc + rounding, (double)maxval);
+        float qc = scaled[i] * Q34;
+        out[i] = (int)FFMIN(qc + rounding, (float)maxval);
         if (is_signed && in[i] < 0.0f) {
             out[i] = -out[i];
         }