multipath: Reload multipathd instead of restart on setup

Multipathd is required by vdsmd.
We should not take care of starting it, but only reloading
new configuration.

Change-Id: I57583eb8931411d40bcce8f6a676621f6ee1eebd
Bug-Url: https://bugzilla.redhat.com/show_bug.cgi?id=988995
Signed-off-by: Yeela Kaplan <ykaplan@redhat.com>
Reviewed-on: http://gerrit.ovirt.org/17487
Reviewed-by: Dan Kenigsberg <danken@redhat.com>