Partly revert b192dc3c

Those objects and shared library handle are not guaranteed to exist
if the Clean() function is called in Open() error path.

modules/audio_output/opensles_android.c

@@ -99,10 +99,14 @@ vlc_module_end ()
 
 static void Clean( aout_sys_t *p_sys )
 {
+    if( p_sys->playerObject )
         Destroy( p_sys->playerObject );
+    if( p_sys->outputMixObject )
         Destroy( p_sys->outputMixObject );
+    if( p_sys->engineObject )
         Destroy( p_sys->engineObject );
 
+    if( p_sys->p_so_handle )
         dlclose( p_sys->p_so_handle );
 
     free( p_sys );