crt: Use native _fseeki64 symbol from msvcrt.dll on Windows Vista+

Function _fseeki64() is available in msvcrt.dll starting from Windows
Vista+. Change the emulation of the _fseeki64() function to use native
symbol when available via the msvcrt_or_emu_glue.h.

Signed-off-by: Martin Storsjö <martin@martin.st>

mingw-w64-crt/stdio/_fseeki64.c

diff --git a/mingw-w64-crt/stdio/_fseeki64.c b/mingw-w64-crt/stdio/_fseeki64.c
index 7b6ad55..3ec4ccb 100644
--- a/mingw-w64-crt/stdio/_fseeki64.c
+++ b/mingw-w64-crt/stdio/_fseeki64.c
@@ -7,7 +7,7 @@
 #include <io.h>
 #include <errno.h>
 
-int __cdecl _fseeki64(FILE* stream, __int64 offset, int whence)
+static int __cdecl emu__fseeki64(FILE *stream, __int64 offset, int whence)
 {
   fpos_t pos;
   if (whence == SEEK_CUR)
@@ -33,4 +33,8 @@
   return fsetpos (stream, &pos);
 }
 
-int __cdecl (*__MINGW_IMP_SYMBOL(_fseeki64))(FILE*, __int64, int) = _fseeki64;
+#define RETT int
+#define FUNC _fseeki64
+#define ARGS FILE *stream, __int64 offset, int whence
+#define CALL stream, offset, whence
+#include "msvcrt_or_emu_glue.h"