locking/rtmutex: Remove rt_mutex_is_locked()

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Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210815211302.552218335@linutronix.de

include/linux/rtmutex.h

@@ -72,17 +72,6 @@ do { \
 #define DEFINE_RT_MUTEX(mutexname) \
 	struct rt_mutex mutexname = __RT_MUTEX_INITIALIZER(mutexname)
 
-/**
- * rt_mutex_is_locked - is the mutex locked
- * @lock: the mutex to be queried
- *
- * Returns 1 if the mutex is locked, 0 if unlocked.
- */
-static inline int rt_mutex_is_locked(struct rt_mutex *lock)
-{
-	return lock->owner != NULL;
-}
-
 extern void __rt_mutex_init(struct rt_mutex *lock, const char *name, struct lock_class_key *key);
 
 #ifdef CONFIG_DEBUG_LOCK_ALLOC