dt-bindings: PCI: qcom: Fix SDX65 compatible

Commit c0aba9f3 ("dt-bindings: PCI: qcom: Add SDX65 SoC") adding
SDX65 was never tested and is clearly bogus.  The qcom,sdx65-pcie-ep
compatible is followed by a fallback in DTS, and there is no driver
matched by this compatible.  Driver matches by its fallback
qcom,sdx55-pcie-ep.  This also fixes dtbs_check warnings like:

  qcom-sdx65-mtp.dtb: pcie-ep@1c00000: compatible: ['qcom,sdx65-pcie-ep', 'qcom,sdx55-pcie-ep'] is too long

[kwilczynski: commit log]
Fixes: c0aba9f3

 ("dt-bindings: PCI: qcom: Add SDX65 SoC")
Link: https://lore.kernel.org/linux-pci/20230827085351.21932-1-krzysztof.kozlowski@linaro.org
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Cc: stable@vger.kernel.org