[SCSI] qla2xxx: Correct vport configuration-change handling.

Upon having configuration changes on vports only, the driver
handles SCR regardless physical port state and, in turn, it
results mailbox error as below:

	Mar 20 11:24:20 dl585 kernel: qla2x00_mailbox_command(9): **** FAILED.  mbx0=4005, mbx1=1, mbx2=8100, cmd=70 ****

With the changes, driver checks physical port loop_state and make
sure the port is ready to take commands.

Signed-off-by: Seokmann Ju <seokmann.ju@qlogic.com>
Signed-off-by: Andrew Vasquez <andrew.vasquez@qlogic.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>