b43: bcma: drop BROKEN

We've fixed the last issue with BCMA support which caused memory
corruption on loading and unloading b43. Support for BCMA in b43 was
tested with 14e4:4353, 14e4:4357, 14e4:4727 and 14e4:4331. First two
cards (BCM43224 and BCM43225) are supported.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>