be2net: refactor MAC-addr setup code

The code to configure the permanent MAC in be_setup() has become quite
complicated, with different FW cmds being used for BEx, SH-R and Lancer.
Simplify the logic by moving some of this complexity to be_cmds.c. This
makes the code in be_setup() a little more readable.

Signed-off-by: Sathya Perla <sathya.perla@emulex.com>
Signed-off-by: David S. Miller <davem@davemloft.net>