PCIe: ASPM: Break out of endless loop waiting for PCI config bits to switch

commit 2a42d9dba7842422ffb2c02e75288a8bc2fd5065 upstream.

Makes a Compaq 6735s boot reliably again.  It used to hang in the loop
on some boots.  Give the link one second to train, otherwise break out
of the loop and reset the previously set clock bits.

Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Matthew Garrett <mjg59@srcf.ucam.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>