PCI: qcom: Enable async probe by default

Qcom PCIe RC driver waits for the PHY link to be up during the probe;
this consumes several milliseconds during boot.

Enable async probe by default so that other drivers can load in parallel
while this driver waits for the link to be up.

Suggested-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20230320064644.5217-1-manivannan.sadhasivam@linaro.org


Tested-by: Johan Hovold <johan+linaro@kernel.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Reviewed-by: Johan Hovold <johan+linaro@kernel.org>