ASoC: allow drivers to compile both static and dynamic

Based on where the code is synced the driver should allow
both static and dynamic linked compilation.
Also remove __exit for modules loaded from another common
init/exit functions.

Change-Id: Ib58f152002aba3af4446f9bbd9b82c279212bd0a
Signed-off-by: Asish Bhattacharya <asishb@codeaurora.org>

dsp/codecs/audio_amrwbplus.c

@@ -394,7 +394,7 @@ int __init audio_amrwbplus_init(void)
 	return ret;
 }
 
-void __exit audio_amrwbplus_exit(void)
+void audio_amrwbplus_exit(void)
 {
 	mutex_destroy(&audio_amrwbplus_ws_mgr.ws_lock);
 	misc_deregister(&audio_amrwbplus_misc);