Add build-dep packages so yum-builddep is effective

yum-builddep doesn't get all of the required packages
needed to build vdsm and vdsm rpms.  Update the specfile
Build-Requires to include the needed packages.

Change-Id: Ia5b96b5b30a9efea06261f40d1f6df61754b8253
Signed-off-by: Ryan Harper <ryanh@us.ibm.com>
Reviewed-on: http://gerrit.ovirt.org/7955
Tested-by: Dan Kenigsberg <danken@redhat.com>
Reviewed-by: Douglas Schilling Landgraf <dougsland@redhat.com>
Reviewed-by: Dan Kenigsberg <danken@redhat.com>