Lots of fixes importing SDL source wholesale into a new iOS project

--HG--
rename : src/libm/math.h => src/libm/math_libm.h

src/main/windows/SDL_windows_main.c

@@ -3,6 +3,9 @@
 
     The WinMain function -- calls your program's main() function
 */
+#include "SDL_config.h"
+
+#ifdef __WIN32__
 
 #include <stdio.h>
 #include <stdlib.h>
@@ -202,4 +205,6 @@ WinMain(HINSTANCE hInst, HINSTANCE hPrev, LPTSTR szCmdLine, int sw)
     return 0;
 }
 
+#endif /* __WIN32__ */
+
 /* vi: set ts=4 sw=4 expandtab: */