tegra: change clocksource driver to be more lowlevel
In order to properly bring up the system PLLs we need a reliable
clocksource. To break the circular dependency between the clocksource
and the CAR driver, get the OSC frequency with a lowlevel function.
Signed-off-by: Lucas Stach <dev@lynxeye.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>