[SCSI] qla4xxx: cache new IP address acquired via DHCP

Prior to firmware state change from ACQUIRING to READY, an
0x8029 AEN is received. Added code to check previous state
being ACQUIRING in order to update the ip address in the driver.

Signed-off-by: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Signed-off-by: Prasanna Mumbai <prasanna.mumbai@qlogic.com>
Signed-off-by: Ravi Anand <ravi.anand@qlogic.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>