UPSTREAM: sched/core: Rename schedutil_cpu_util() and allow rest of the kernel to use it

There is nothing schedutil specific in schedutil_cpu_util(), rename it
to effective_cpu_util(). Also create and expose another wrapper
sched_cpu_util() which can be used by other parts of the kernel, like
thermal core (that will be done in a later commit).

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lkml.kernel.org/r/db011961fb3bb8bef1c0eda5cd64564637d3ef31.1607400596.git.viresh.kumar@linaro.org


(cherry picked from commit a5418be9)

BUG=b:249685960
TEST=Build

Change-Id: I855c0f8d944a0737041a07df4a080a0cda45f1be
Signed-off-by: Masami Hiramatsu <mhiramat@google.com>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/kernel/+/3939323


Reviewed-by: Sean Paul <sean@poorly.run>
Reviewed-by: Suleiman Souhlal <suleiman@chromium.org>