linux-phytec-ti

Documentation: PCI: Add specification for the *PCI NTB* function device

Add specification for the *PCI NTB* function device. The endpoint function
driver and the host PCI driver should be created based on this
specification.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>