staging: tidspbridge: request dmtimer clocks on init

Given that dm timer framework doesn't support request of clocks
by soft | hard irqs because some recent changes, tidspbridge needs
to request its clocks on init and enable/disable them on demand.

This was first seen on 3.2-rc1.

Signed-off-by: Omar Ramirez Luna <omar.ramirez@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>