8250_pci: Added driver for Endrun Technologies PTP PCIe card.

Added recognition of EndRun Technologies PCIe PTP slave card
and setup two ttySx ports for communication with the card for
retrieval of PTP based time and to communicate with the card's
Linux OS.

Signed-off-by: Mike Skoog <mskoog@endruntechnologies.com>
Signed-off-by: Mike Korreng <mkorreng@endruntechnologies.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>