ARM: Remove temporary sched_clock.h header

This header file is no longer needed now that the ARM sched_clock
framework is generic and all users have moved to linux/sched_clock.h
instead of asm/sched_clock.h. Remove it.
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NKevin Hilman <khilman@linaro.org>

arch/arm/include/asm/sched_clock.h

-/* You shouldn't include this file. Use linux/sched_clock.h instead.
- * Temporary file until all asm/sched_clock.h users are gone
- */
-#include <linux/sched_clock.h>