flac, mpc, ogg, wavpack: include unistd.h for SEEK_SET

SEEK_SET is defined by unistd.h.  Explicitly include it.

src/decoder/flac_plugin.c

@@ -19,6 +19,7 @@
 #include "_flac_common.h"
 
 #include <assert.h>
+#include <unistd.h>
 
 /* this code was based on flac123, from flac-tools */
 

src/decoder/mpc_plugin.c

@@ -20,6 +20,7 @@
 
 #include <mpcdec/mpcdec.h>
 #include <glib.h>
+#include <unistd.h>
 
 typedef struct _MpcCallbackData {
 	struct input_stream *inStream;

src/decoder/oggflac_plugin.c

@@ -23,6 +23,7 @@
 #include "_ogg_common.h"
 
 #include <OggFLAC/seekable_stream_decoder.h>
+#include <unistd.h>
 
 static void oggflac_cleanup(FlacData * data,
 			    OggFLAC__SeekableStreamDecoder * decoder)

src/decoder/oggvorbis_plugin.c

@@ -38,6 +38,7 @@
 #include <glib.h>
 #include <errno.h>
 #include <stdlib.h>
+#include <unistd.h>
 
 #ifdef WORDS_BIGENDIAN
 #define OGG_DECODE_USE_BIGENDIAN	1

src/decoder/wavpack_plugin.c

@@ -24,6 +24,7 @@
 
 #include <wavpack/wavpack.h>
 #include <glib.h>
+#include <unistd.h>
 
 /* pick 1020 since its devisible for 8,16,24, and 32-bit audio */
 #define CHUNK_SIZE		1020