powerpc/pseries/eeh: Propagate needs_freset flag to device at PE

  For multifunction adapters with a PCI bridge or switch as the device
  at the Partitionable Endpoint(PE), if one or more devices below PE
  sets dev->needs_freset, that value will be set for the PE device.

  In other words, if any device below PE requires a fundamental reset
  the PE will request a fundamental reset.

Signed-off-by: Richard A Lary <rlary@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>