inital, almost working cross-compilation setup with Visual Studio and cmake

prebuilt/windows/SDL3-static/lib/pkgconfig/sdl3.pc

@@ -0,0 +1,13 @@
+prefix=${pcfiledir}/../..
+exec_prefix=${prefix}
+libdir=${prefix}/lib
+includedir=${prefix}/include
+
+Name: sdl3
+Description: Simple DirectMedia Layer is a cross-platform multimedia library designed to provide low level access to audio, keyboard, mouse, joystick, 3D hardware via OpenGL, and 2D video framebuffer.
+URL: https://www.libsdl.org/
+Version: 3.5.0
+Requires.private: 
+Conflicts:
+Libs: -L${libdir}  -lSDL3-static   -lkernel32 -luser32 -lgdi32 -lwinmm -limm32 -lole32 -loleaut32 -lversion -luuid -ladvapi32 -lsetupapi -lshell32 -lhid -ldinput8
+Cflags: -I${includedir}