PCI: pciehp: Drop pointless label from pciehp_probe()

The err_out_none label in pciehp_probe() only leads to a return statement,
so use return statements instead of jumps to it and drop it.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>