sched/tune: access schedtune_initialized under CGROUP_SCHEDTUNE

schedtune_initialized is protected by CONFIG_CGROUP_SCHEDTUNE, but
is being used without CONFIG_CGROUP_SCHEDTUNE being defined. Add
appropriate ifdefs around the usage of schedtune_initialized to
avoid a compilation error when CONFIG_CGROUP_SCHEDTUNE is not
defined.

Change-Id: Iab79bf053d74db3eeb84c09d71d43b4e39746ed2
Signed-off-by: Russ Weight <russell.h.weight@intel.com>
Signed-off-by: Fei Yang <fei.yang@intel.com>

Author: Russ Weight

kernel/sched/fair.c

@@ -5668,7 +5668,11 @@ static inline int __energy_diff(struct energy_env *eenv)
 #ifdef CONFIG_SCHED_TUNE
 
 struct target_nrg schedtune_target_nrg;
+
+#ifdef CONFIG_CGROUP_SCHEDTUNE
 extern bool schedtune_initialized;
+#endif /* CONFIG_CGROUP_SCHEDTUNE */
+
 /*
  * System energy normalization
  * Returns the normalized value, in the range [0..SCHED_CAPACITY_SCALE],
@@ -5679,9 +5683,11 @@ normalize_energy(int energy_diff)
 {
 	u32 normalized_nrg;
 
+#ifdef CONFIG_CGROUP_SCHEDTUNE
 	/* during early setup, we don't know the extents */
 	if (unlikely(!schedtune_initialized))
 		return energy_diff < 0 ? -1 : 1 ;
+#endif /* CONFIG_CGROUP_SCHEDTUNE */
 
 #ifdef CONFIG_SCHED_DEBUG
 	{