Fix running regression tests on remote targets

Originally committed as revision 18251 to svn://svn.ffmpeg.org/ffmpeg/trunk

tests/codec-regression.sh

@@ -29,7 +29,7 @@ bench2="$datadir/$this.bench2.tmp"
 raw_src="${target_path}/$3/%02d.pgm"
 raw_dst="$datadir/$this.out.yuv"
 raw_ref="$datadir/$2.ref.yuv"
-pcm_src="$datadir/asynth1.sw"
+pcm_src="$target_datadir/asynth1.sw"
 pcm_dst="$datadir/$this.out.wav"
 pcm_ref="$datadir/$2.ref.wav"
 crcfile="$datadir/$this.crc"