linux: update to v4.2.4-openpower1

 - Rebased on upstream stable release v4.2.4
 - Upstream commit "8c24d6d7b09d usb: xhci: stop everything on the first
   call to xhci_stop" means that our patch "xhci: do not halt the
   secondary HCD" is no longer required

Signed-off-by: Joel Stanley <joel@jms.id.au>
24 files changed