x86: OLPC: convert olpc-xo1 driver from pci device to platform device

The cs5535-mfd driver now takes care of the PCI BAR handling; this
means the olpc-xo1 driver shouldn't be touching the PCI device at all.

This patch uses both cs5535-acpi and cs5535-pms platform devices rather
than a single platform device because the cs5535-mfd driver may be used
by other CS5535 platform-specific drivers; OLPC doesn't get to dictate
that ACPI and PMS will always be used together.

Signed-off-by: Andres Salomon <dilinger@queued.net>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>