Enable IO multipathing

When adding 3rd part SAN devices, the file /kernel/drv/scsi_vhci.conf needs to be edited to add multipathing support and then 'stmsboot -e' needs to be executed, which requires a reboot:

System Administration Commands stmsboot(1M)

NAME
stmsboot - administration program for the Solaris I/O mul-
tipathing feature

SYNOPSIS
/usr/sbin/stmsboot
[-d | -e | -u | -L | -l controller_number]

DESCRIPTION
The Solaris I/O multipathing feature is a multipathing solu-
tion for storage devices that is part of the Solaris operat-
ing environment. This feature was formerly known as Sun
StorEdge Traffic Manager (STMS) or MPxIO.

The stmsboot program is an administrative command to manage
enumeration of fibre channel devices under Solaris I/O mul-
tipathing. Solaris I/O multipathing-enabled devices are
enumerated under scsi_vhci(7D), providing multipathing capa-
bilities. Solaris I/O multipathing-disabled devices are
enumerated under the physical controller.

In the /dev and /devices trees, Solaris I/O multipathing-
enabled devices receive new names that indicate that they
are under Solaris I/O multipathing control. This means a
device will have a different name from its original name
(following installation) when it is under Solaris I/O mul-
tipathing control. The stmsboot command automatically
updates /etc/vfstab and dump configuration to reflect the
device names changes when enabling or disabling Solaris I/O
multipathing. A reboot is required for changes to take
effect.