add KIVY_CROSS_PLATFORM

Author: DexerBR

pythonforandroid/recipes/kivy/__init__.py

@@ -58,6 +58,7 @@ def get_recipe_env(self, arch, **kwargs):
 
         # NDKPLATFORM is our switch for detecting Android platform, so can't be None
         env['NDKPLATFORM'] = "NOTNONE"
+        env['KIVY_CROSS_PLATFORM'] = 'android'
         if 'sdl2' in self.ctx.recipe_build_order:
             env['USE_SDL2'] = '1'
             env['KIVY_SPLIT_EXAMPLES'] = '1'