PCI: qcom: Add support for SA8540P

PCI: qcom: Add support for SA8540P

The SA8540P platform has five PCIe controllers: two 4-lane, two 2-lane
and one 1-lane.

Add a new "qcom,pcie-sa8540p" compatible string and reuse the 1.9.0 ops.

Note that like for SC8280XP, the SA8540P controllers need two or three
interconnect clocks to be enabled.

Link: https://lore.kernel.org/r/20220714071348.6792-6-johan+linaro@kernel.org
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Brian Masney <bmasney@redhat.com>
Acked-by: Stanimir Varbanov <svarbanov@mm-sol.com>