swr: move AudioConvert to header

the next commits will need it
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libswresample/audioconvert.c

@@ -32,15 +32,6 @@
 #include "audioconvert.h"
 
 
-typedef void (conv_func_type)(uint8_t *po, const uint8_t *pi, int is, int os, uint8_t *end);
-
-struct AudioConvert {
-    int channels;
-    conv_func_type *conv_f;
-    const int *ch_map;
-    uint8_t silence[8]; ///< silence input sample
-};
-
 #define CONV_FUNC_NAME(dst_fmt, src_fmt) conv_ ## src_fmt ## _to_ ## dst_fmt
 
 //FIXME rounding ?

libswresample/audioconvert.h

@@ -33,8 +33,15 @@
 #include "libavutil/cpu.h"
 #include "libavutil/audioconvert.h"
 
-struct AudioConvert;
-typedef struct AudioConvert AudioConvert;
+
+typedef void (conv_func_type)(uint8_t *po, const uint8_t *pi, int is, int os, uint8_t *end);
+
+typedef struct AudioConvert {
+    int channels;
+    conv_func_type *conv_f;
+    const int *ch_map;
+    uint8_t silence[8]; ///< silence input sample
+}AudioConvert;
 
 /**
  * Create an audio sample format converter context