Add mhp_pc_dimm_assigned_slot & mhp_pc_dimm_assigned_address
events to trace which address and slot where assigned to
plugged in PC_DIMM device on target-i386 machine.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>