Add MAINTAINERS entry for Qualcomm PCIe Endpoint driver and its devicetree
binding.  Also fix the PCIe RC entry to cover only the RC driver.

Link: https://lore.kernel.org/r/20210920065946.15090-4-manivannan.sadhasivam@linaro.orgSigned-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>