Fix PDF ouput when cross-compiling with mingw

Need to use __WIN32__ instead of _MSC_VER to select _snprintf in
place of snprintf when cross compiling. Otherwise all all %ld
arguments get misprinted resulting in broken PDF output.

src/cairo-compiler-private.h

@@ -111,8 +111,11 @@ CAIRO_BEGIN_DECLS
 #define __attribute__(x)
 #endif
 
-#ifdef _MSC_VER
+#ifdef __WIN32__
 #define snprintf _snprintf
+#endif
+
+#ifdef _MSC_VER
 #undef inline
 #define inline __inline
 #endif

src/cairo-output-stream.c

@@ -36,16 +36,13 @@
 #include "cairoint.h"
 
 #include "cairo-output-stream-private.h"
+#include "cairo-compiler-private.h"
 
 #include <stdio.h>
 #include <locale.h>
 #include <ctype.h>
 #include <errno.h>
 
-#ifdef _MSC_VER
-#define snprintf _snprintf
-#endif /* _MSC_VER */
-
 
 void
 _cairo_output_stream_init (cairo_output_stream_t            *stream,