qualcommax: ipq807x: fix Gen2 PCIe port

qualcommax: ipq807x: fix Gen2 PCIe port

Gen2 PCIe port recently got broken on IPQ807x during update to 6.1.39 as
upstream backported:
("PCI: qcom: Remove PCIE20_ prefix from register definitions") [1]

So, fix it by adding a pending upstream fix for it [2].

[1] https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/drivers/pci/controller/dwc/pcie-qcom.c?h=v6.1.39&id=db962c7a711c3393a80a18219960cd54fb33c53d
[2] https://patchwork.kernel.org/project/linux-arm-msm/patch/20230724063429.3980462-1-quic_srichara@quicinc.com/

Fixes: fec22f8375b4 ("kernel: bump 6.1 to 6.1.39")
Signed-off-by: Robert Marko <robimarko@gmail.com>