scsi: qla2xxx: Reduce fabric scan duplicate code

scsi: qla2xxx: Reduce fabric scan duplicate code

For fabric scan, current code uses switch scan opcode and flags as the
method to iterate through different commands to carry out the process.
This makes it hard to read. This patch convert those opcode and flags into
steps. In addition, this help reduce some duplicate code.

Consolidate routines that handle GPNFT & GNNFT.

Cc: stable@vger.kernel.org
Signed-off-by: Quinn Tran <qutran@marvell.com>
Signed-off-by: Nilesh Javali <njavali@marvell.com>
Link: https://lore.kernel.org/r/20240710171057.35066-10-njavali@marvell.com
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>