The LVM driver is reporting incorrect target_portal and target_portals
entries for IPv6 with all the targets, as it is not enclosing the
address in square brackets making it impossible for iscsiadm in OS-Brick
to tell the port appart from the IP address.
This patch makes sure that IPv6 addresses in target_portal and
target_portals are properly formatted in the [IPv6_address]:port when
the IPv6_address does not already include the square brackets.
This fix affects all the targets: IET, LIO, TGT, CXT, and SCST.
Closes-Bug: #1696866
Change-Id: Ie7053c813af8c99b5545222d4724b71061348a09
(cherry picked from commit fddb9b7962)