be2net: Fix FW flashing on Skyhawk-R

FW flash layout on Skyhawk-R is different from BE3-R.
Hence the code needs to be fixed to flash FW on Skyhawk-R.
Also cleaning up code in BE3-R flashing function.

Signed-off-by: Vasundhara Volam <vasundhara.volam@emulex.com>
Signed-off-by: Padmanabh Ratnakar <padmanabh.ratnakar@emulex.com>
Signed-off-by: David S. Miller <davem@davemloft.net>