ALSA: fireworks/bebob/oxfw/dice: enable to make as built-in

ALSA: fireworks/bebob/oxfw/dice: enable to make as built-in

When committed to upstream, these four modules had wrong entries for
Makefile. This forces them to be loadable modules even if they're set
as built-in.

This commit fixes this bug.

Fixes: 8b870342950c('ALSA: fireworks: Add skelton for Fireworks based devices')
Fixes: 14920c6a6f94('ALSA: bebob: Add skelton for BeBoB based devices')
Fixes: e1ea8a81b5d0('ALSA: oxfw: Move to its own directory')
Fixes: 4c5184d18c85('ALSA: dice: Move file to its own directory')
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>