This patch fixes the issue that a reverted patch was causing [0].
In this patch we add a check for partitions which are not having
mountpoints and propably was causing the problem in airship-seaworthy.
[0] https://review.openstack.org/#/c/610594/
Story: #2002951
Change-Id: Ic3055ebdcf37461f52391cf564c29f8283637684
Signed-off-by: Dimitrios Markou <mardim@intracom-telecom.com>