webadmin: Fix fencing policy fields alignment

Fixes alignment of field in Fencing Policy tab in Cluster popup view.
This problem appears only in Firefox 31 in RHEL 6.

Change-Id: Icc5fb79a89c4b6e8fc710f02ce0e59fe5bfed95f
Bug-Url: https://bugzilla.redhat.com/1139699
Signed-off-by: Martin Perina <mperina@redhat.com>