futex: Make futex_private_hash_get() static

futex_private_hash_get() is not used outside if its compilation unit.
Make it static.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250710110011.384614-4-bigeasy@linutronix.de

Author: Sebastian Andrzej Siewior

kernel/futex/core.c

@@ -143,7 +143,7 @@ static inline bool futex_key_is_private(union futex_key *key)
 	return !(key->both.offset & (FUT_OFF_INODE | FUT_OFF_MMSHARED));
 }
 
-bool futex_private_hash_get(struct futex_private_hash *fph)
+static bool futex_private_hash_get(struct futex_private_hash *fph)
 {
 	if (fph->immutable)
 		return true;

kernel/futex/futex.h

@@ -228,14 +228,12 @@ extern void futex_hash_get(struct futex_hash_bucket *hb);
 extern void futex_hash_put(struct futex_hash_bucket *hb);
 
 extern struct futex_private_hash *futex_private_hash(void);
-extern bool futex_private_hash_get(struct futex_private_hash *fph);
 extern void futex_private_hash_put(struct futex_private_hash *fph);
 
 #else /* !CONFIG_FUTEX_PRIVATE_HASH */
 static inline void futex_hash_get(struct futex_hash_bucket *hb) { }
 static inline void futex_hash_put(struct futex_hash_bucket *hb) { }
 static inline struct futex_private_hash *futex_private_hash(void) { return NULL; }
-static inline bool futex_private_hash_get(void) { return false; }
 static inline void futex_private_hash_put(struct futex_private_hash *fph) { }
 #endif