netxen_nic: Allow only useful and recommended firmware dump capture mask values

o 0x3, 0x7, 0xF, 0x1F, 0x3F, 0x7F and 0xFF are the allowed capture masks.

Signed-off-by: Manish chopra <manish.chopra@qlogic.com>
Signed-off-by: Rajesh Borundia <rajesh.borundia@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>