PCI/pwrctrl: Fix device leak at device stop

Make sure to drop the reference to the pwrctrl device taken by
of_find_device_by_node() when stopping a PCI device.

Fixes: 681725a ("PCI/pwrctl: Remove pwrctl device without iterating over all children of pwrctl parent")
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
Cc: stable@vger.kernel.org	# v6.13
Link: https://patch.msgid.link/20250721153609.8611-4-johan+linaro@kernel.org

Author: jhovold

drivers/pci/remove.c

@@ -31,6 +31,8 @@ static void pci_pwrctrl_unregister(struct device *dev)
 		return;
 
 	of_device_unregister(pdev);
+	put_device(&pdev->dev);
+
 	of_node_clear_flag(np, OF_POPULATED);
 }