msm: pm-8x60: Change init call to late_initcall

Clock driver has moved to drivers directly. pm-8x60 depends on clock
API during probe, and can't do deferred probing yet. In order to
guarantee the right ordering, move msm_pm_8x60_init to late_initcall.

Change-Id: I42a61dbf3302ef1554c726b05a47d9173f757011
Signed-off-by: Junjie Wu <junjiew@codeaurora.org>