dt-bindings: PCI: ti,am65: Convert PCIe host/endpoint mode dt-bindings to YAML

Convert PCIe host/endpoint mode dt-bindings for TI's AM65/Keystone SoC
to YAML binding.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Link: https://lore.kernel.org/r/20210603133450.24710-1-kishon@ti.com


Signed-off-by: Rob Herring <robh@kernel.org>