fix(iscsiadm): separate merged options (--logoutall--show → --logoutall --show)

[ADI2705]

Description

Fix incorrect option concatenation in iscsiadm bash completion.

In node mode, the options --logoutall and --show are incorrectly merged in the completion script as:
--logoutall--show

This happens due to a missing space between the two options in:
completions-core/iscsiadm.bash

---

Fixes #1611

Problem

Because of this concatenation:

• Bash treats --logoutall--show as a single invalid option
• Tab completion suggestions become incorrect
• In some cases, repeated or malformed completions may be inserted into the command line

---

Fix

This patch separates the options correctly by adding a space:

- --logoutall--show
+ --logoutall --show