Win Service Script: Revise help for /host

The help text for the /host parameter is misleading.

The current help text for the /host parameter is:

/host [^<domainhost^>] : Indicates that domain mode is to be used with an optional domain controller name.

A better description would be:

Indicates that domain mode is to be used, with an optional domain/host controller name.

6.4 Bug: https://bugzilla.redhat.com/show_bug.cgi?id=1375439
Customer support case: 01676698