b43: probe bcma core (device) rev 0x15

OpenWrt user reported b43 doesn't probe wireless core on SoC BCM5356A1:
[    0.000000] bcma: bus0: Found chip with id 0x5356, rev 0x01 and package 0x04
it is because this chip uses different 802.11 core revison than others:
[    0.000000] bcma: bus0: Core 1 found: IEEE 802.11 (manuf 0x4BF, id 0x812, rev 0x15, class 0x0)

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>