PCI: mobiveil: Add Mobiveil PCIe Host Bridge IP driver DT bindings

Add DT bindings for the Mobiveil PCIe Host Bridge IP driver and update the
vendor prefixes file.

Signed-off-by: Subrahmanya Lingappa <l.subrahmanya@mobiveil.co.in>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rob Herring <robh@kernel.org>