opp: Add dev_pm_opp_of_add_table_noclk()

A few drivers have device's clk but they don't want the OPP core to
handle that. Add a new helper for them, dev_pm_opp_of_add_table_noclk().

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Dmitry Osipenko <digetx@gmail.com>