Prepare for embedded use of the AR9285/AR9287.

Prepare for embedded use of the AR9285/AR9287.

Calibration/PCI data that's written to flash (rather than EEPROM attached
to the NIC) is typically already in host-endian. The existing checks
end up swapping 16 bit words incorrectly - the correct solution would be
to read the magic value and determine the EEPROM endianness from that.
(This is what Linux does.)

This doesn't completely enable embedded use of the AR9285/AR9287 -
notably, the EEPROM read methods need to be made generic and available
to all EEPROM drivers. I'll worry about that later.

Approved by:	re (kib)