bcm4306 cards are ambiguous. BCM4306 rev 2 requires bwi. BCM4306 rev
3 will work with either. Since we can't easily determine which is
which, just remove them.
a solution is using PIO mode. As fas as I know all open source based
broadcom drivers for specially LP PHY has this issue because it's
a reverse engineered driver from wl(4).
Pointed by: Warren Block <wblock at wonkity.com>
o uses v4 firmware instead of v3. A port will be committed to create
the bwn firmware module.
o supports B/G and LP(low power) PHYs.
o supports 32 / 64 bits DMA operations.
o tested on big / little endian machines so should work on all
architectures.
It'd not connected to the build until the firmware port is committed.
