The 32 bit sched_clock interface now supports 64 bits. Upgrade to
the 64 bit function to allow us to remove the 32 bit registration
interface.

Cc: Eric Miao <eric.y.miao@gmail.com>
Cc: Haojian Zhuang <haojian.zhuang@gmail.com>
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NKevin Hilman <khilman@linaro.org>