kernel/condition_variable: Make ConditionVariableEntry::Variable non-inline.

We have to use an atomic here.

headers/private/kernel/condition_variable.h

@@ -33,7 +33,7 @@ public:
 			status_t			Wait(const void* object, uint32 flags = 0,
 									bigtime_t timeout = 0);
 
-	inline	ConditionVariable*	Variable() const { return fVariable; }
+			ConditionVariable*	Variable() const;
 
 private:
 	inline	void				_AddToLockedVariable(ConditionVariable* variable);

src/system/kernel/condition_variable.cpp

@@ -129,6 +129,13 @@ ConditionVariableEntry::Add(const void* object)
 }
 
 
+ConditionVariable*
+ConditionVariableEntry::Variable() const
+{
+	return atomic_pointer_get(&fVariable);
+}
+
+
 inline void
 ConditionVariableEntry::_AddToLockedVariable(ConditionVariable* variable)
 {