sandy/ivy: Fix PIRQs on Chromebooks

This partially reverts commit 33b535f1. After this commit, samsung/lumpy had its
internal USB EHCI controller broken, with no assigned IRQ.

PIRQA-PIRQH may be wired as edge-triggered interrupts, making them exclusive
for the GPIO to use. They cannot be used for PCI devices at the same time.

Change-Id: Ic90343401ac20ca8673baf927cd7703c3481aeab
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: http://review.coreboot.org/9993
Reviewed-by: Nicolas Reinecke <nr@das-labor.org>
Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Tested-by: build bot (Jenkins)
18 files changed