ALSA: i2c: Remove empty init and exit

For a sake of code simplification, remove the init and the exit
entries that do nothing.

Notes for readers: actually it's OK to remove *both* init and exit,
but not OK to remove the exit entry.  By removing only the exit while
keeping init, the module becomes permanently loaded; i.e. you cannot
unload it any longer!

Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/i2c/other/ak4xxx-adda.c

@@ -911,15 +911,3 @@ int snd_akm4xxx_build_controls(struct snd_akm4xxx *ak)
 	return 0;
 }
 EXPORT_SYMBOL(snd_akm4xxx_build_controls);
-
-static int __init alsa_akm4xxx_module_init(void)
-{
-	return 0;
-}
-        
-static void __exit alsa_akm4xxx_module_exit(void)
-{
-}
-        
-module_init(alsa_akm4xxx_module_init)
-module_exit(alsa_akm4xxx_module_exit)