Added additional platform check for __ANDROID__.

The macro ANDROID was deprecated with "android-ndk-1.6_r1".

include/SDL_platform.h

@@ -60,7 +60,7 @@
 #undef __LINUX__
 #define __LINUX__   1
 #endif
-#if defined(ANDROID)
+#if defined(ANDROID) || defined(__ANDROID__)
 #undef __ANDROID__
 #undef __LINUX__ /* do we need to do this? */
 #define __ANDROID__ 1