ARM: i.MX53: split lowlevel function into early/nonearly version
clock_notifier_call_chain() can't be called before init time. Protecting
it with IS_ENABLED(__PBL__) is not enough. This patch splits out a new
imx53_init_lowlevel_early which can be called before init time and does
not have the call to clock_notifier_call_chain() in it.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>