fix LUN handling (byte order issue)

now ch0 on a NEOSeries FlexStor II is detected again on LUN 1
this is a regression introduced in 1.15 update and 1.8.10.3 pullup

Tested with NEOSeries FlexStor II:
mpii0 at pci1 dev 0 function 0: vendor 1000 product 00ab (rev. 0x01)
mpii0: interrupting at irq 11
mpii0: HBA 9400-8i8e, firmware 3.0.4.0, MPI 2.6
mpii0: physical disk inserted in slot 9
mpii0: physical disk inserted in slot 13
mpii0: physical disk inserted in slot 16
st0 at scsibus0 target 9 lun 0: <IBM, ULTRIUM-HH7, J4D1> tape removable
st0: drive empty
st0: tagged queueing
st1 at scsibus0 target 13 lun 0: <IBM, ULTRIUM-HH7, J4D1> tape removable
st1: drive empty
ch0 at scsibus0 target 13 lun 1: <BDT, FlexStor II, 5.50> changer removable
ch0: 23 slots, 2 drives, 1 picker, 1 portal
st1: tagged queueing
ch0: tagged queueing
ses0 at scsibus0 target 16 lun 0: <LSI, VirtualSES, 01> enclosure services fixed
ses0: SCSI-3 SES Device

(kardel)