net: ethernet: bgmac: convert to feature flags

The bgmac driver is using the bcma provides device ID and revision, as
well as the SoC ID and package, to determine which features are
necessary to enable, reset, etc in the driver.   In anticipation of
removing the bcma requirement for this driver, these must be changed to
not reference that struct.  In place of that, each "feature" has been
given a flag, and the flags are enabled for their respective device and
SoC.

Signed-off-by: Jon Mason <jon.mason@broadcom.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>