clk: qoriq: add cpufreq platform device

Add a platform device for qoirq-cpufreq driver for the compatible
clockgen blocks.

Reviewed-by: Yuantian Tang <andy.tang@nxp.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Mian Yousaf Kaukab <ykaukab@suse.de>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>