scsi: qla2xxx: Fix memory size truncation

Memory size calculations for Extended Login used in hardware offload got
truncated. Fix this by changing definition of exlogin_size to use uint32_t.

Link: https://lore.kernel.org/r/20200904045128.23631-7-njavali@marvell.com
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Quinn Tran <qutran@marvell.com>
Signed-off-by: Nilesh Javali <njavali@marvell.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>