cpufreq: sh: Remove unused linux/sched.h headers

Since commit '205dcc1ecbc5(cpufreq/sh: Replace racy task affinity logic)'
the header <linux/sched.h> is useless in sh-cpufreq.c, so remove it.

Signed-off-by: Hailong Liu <liu.hailong6@zte.com.cn>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/cpufreq/sh-cpufreq.c

@@ -23,7 +23,6 @@
 #include <linux/cpumask.h>
 #include <linux/cpu.h>
 #include <linux/smp.h>
-#include <linux/sched.h>	/* set_cpus_allowed() */
 #include <linux/clk.h>
 #include <linux/percpu.h>
 #include <linux/sh_clk.h>