PCI: qcom: Prevent use of uninitialized data in qcom_pcie_suspend_noirq()

PCI: qcom: Prevent use of uninitialized data in qcom_pcie_suspend_noirq()

Smatch complains that "ret" could be uninitialized if "pcie->icc_mem" is
NULL and "pm_suspend_target_state == PM_SUSPEND_MEM".

Silence this warning by initializing ret to zero.

Fixes: 78b5f6f8855e ("PCI: qcom: Add OPP support to scale performance")
Link: https://lore.kernel.org/linux-pci/20240708180539.1447307-4-dan.carpenter@linaro.org
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: Anders Roxell <anders.roxell@linaro.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>