netxen: remove old flash check.

Remove flash size check which made sense only for ancient
boards with 1MB flash. The check is based on values read
from specific locations and fails with firmware size changes.

This prevents driver from getting right mac addresses.

Signed-off-by: Dhananjay Phadke <dhananjay@netxen.com>
Signed-off-by: David S. Miller <davem@davemloft.net>