b43: Kconfig: drop unknown symbol 'BRCMSMAC_MODULE'

There's no Kconfig symbol BRCMSMAC_MODULE, so the check for it will
always fail. There's no need to append _MODULE to tristate symbols
anyhow, because the config tools will do the right thing automagically.

(While we're touching this Kconfig file replace a tab between "default"
and "y" with a space.)

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>