core: Update host kdump status during vdsGetCaps

Kdump status of host is updated when vdsGetCaps is called.

Change-Id: Ib5f3c0aad602c8797225e3311ecb5f307d765123
Bug-Url: https://bugzilla.redhat.com/1079821
Signed-off-by: Martin Perina <mperina@redhat.com>