OMAP: PM: disable idle on suspend for GPIO and UART

Until these drivers are runtime PM converted, their device power
states are managed by calling custom driver hooks late in the
idle/suspend path.  Therefore, do not let the suspend/resume core code
automatically idle these devices since they will be managed manually
by the OMAP PM core very late in the idle/suspend path.

Signed-off-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>