sched/cpupri: Remove unnecessary definitions in cpupri.h

sched/cpupri: Remove unnecessary definitions in cpupri.h

Actually, cpupri_set() and cpupri_init() can never be used without
CONFIG_SMP.

Signed-off-by: pang.xunlei <pang.xunlei@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Juri Lelli <juri.lelli@gmail.com>
Cc: "pang.xunlei" <pang.xunlei@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1415260327-30465-1-git-send-email-pang.xunlei@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>