Centralizes fetching of board information (vendor, type, revision, etc),
and adds support for matching quirks against board identification info.
- Adds a BHND_BUS_READ_BOARD_INFO(), allowing bhnd bus/bus parent(s) to handle implementation-specific fetching of board info.
- Integrates board type constants from the latest Broadcom ISC-licensed bcmdevs.h included in dd-wrt's Broadcom driver source drops.
- Adds support for matching on chip/board quirks to bhnd_device_quirks()/bhnd_chip_quirks().
- Use the new board/chip quirk matching to match Apple devices that failed to set BFL2_PCIEWAR_OVR in SROM.
Depends on D6246