avcodec/ac3dec: avoid #if, use if() instead, its cleaner and shorter

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Signed-off-by: Nedeljko Babic <nbabic@mips.com>

libavcodec/ac3dec.c

@@ -873,9 +873,8 @@ static int decode_audio_block(AC3DecodeContext *s, int blk)
 
             s->spx_dst_start_freq = dst_start_freq;
             s->spx_src_start_freq = src_start_freq;
-#if !USE_FIXED
+            if (!USE_FIXED)
                 s->spx_dst_end_freq   = dst_end_freq;
-#endif
 
             decode_band_structure(gbc, blk, s->eac3, 0,
                                   start_subband, end_subband,