PCI: qcom: Fix runtime PM imbalance on error

pm_runtime_get_sync() increments the runtime PM usage counter even
when it returns an error code, thus a matching decrement is needed on
the error handling path to keep the counter balanced.

Link: https://lore.kernel.org/r/20200707055000.9453-1-dinghao.liu@zju.edu.cn


Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>