ANDROID: Guard rq_clock_task_mult with CONFIG_SMP

rq->cpu only exists on CONFIG_SMP builds. PELT only needs to support
SMP-enabled builds, so guard rq_clock_task_mult with CONFIG_SMP to
support compilation of kernel without CONFIG_SMP enabled.

Change-Id: I7779f5b10b44757dfd4cbc159b6ae3f3f1ddf3e7
Fixes: 9377277724 ("ANDROID: sched: Introducing PELT multiplier")
Signed-off-by: Elliot Berman <quic_eberman@quicinc.com>

kernel/sched/sched.h

@@ -1193,6 +1193,7 @@ static inline u64 rq_clock_task(struct rq *rq)
 	return rq->clock_task;
 }
 
+#ifdef CONFIG_SMP
 DECLARE_PER_CPU(u64, clock_task_mult);
 
 static inline u64 rq_clock_task_mult(struct rq *rq)
@@ -1202,6 +1203,7 @@ static inline u64 rq_clock_task_mult(struct rq *rq)
 
 	return per_cpu(clock_task_mult, cpu_of(rq));
 }
+#endif
 
 /**
  * By default the decay is the default pelt decay period.