UI: set correct SSH trust target path in tooltip.

Fixing the path displayed in Install Host form SSH PublicKey field
tooltip to the correct value (from .ssh/authorized_keys to
/root/.ssh/authorized_keys)

Change-Id: I835be95c56978e26a8c849fdbccbdff8a70f5c66
Bug-Url: https://bugzilla.redhat.com/show_bug.cgi?id=1068763
Signed-off-by: Eli Mesika <emesika@redhat.com>