linux: add support for Ubiquiti WifiStation

Signed-off-by: Stephan Raue <stephan@openelec.tv>
bcm2835-driver: update to bcm2835-driver-86e7643

Signed-off-by: Stephan Raue <stephan@openelec.tv>
bcm2835-bootloader: update to bcm2835-bootloader-86e7643

Signed-off-by: Stephan Raue <stephan@openelec.tv>