Fix pcm_read_seek () when the position it calculates is greater than 2 GB.

pcm_read_seek() puts the return value of url_fseek() in an int and then
compares < 0 to see if an error occurred; if the position is greater
than 2 GB, the 32-bit signed int result will be < 0.

Change the type of ret to int64_t to avoid the wraparound.

patch by Daniel Verkamp, daniel drv nu

Originally committed as revision 20169 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavformat/raw.c

@@ -219,8 +219,8 @@ int pcm_read_seek(AVFormatContext *s,
                   int stream_index, int64_t timestamp, int flags)
 {
     AVStream *st;
-    int block_align, byte_rate, ret;
-    int64_t pos;
+    int block_align, byte_rate;
+    int64_t pos, ret;
 
     st = s->streams[0];