ANDROID: Remove duplicate _system->quit() from JNI::Destroy()

Since it is already called in Jni::main after scummvm_main() returns. The second call in destroy caused crashes on some devices.

backends/platform/android/jni.cpp

@@ -562,7 +562,6 @@ void JNI::destroy(JNIEnv *env, jobject self) {
 	delete _asset_archive;
 	_asset_archive = 0;
 
-	_system->quit();
 	delete _system;
 	g_system = 0;
 	_system = 0;