feat(locks): add bitlock

This patch adds 'bitlock_t' type and bit_lock() and
bit_unlock() to support locking/release functionality
based on individual bit position. These functions use
atomic bit set and clear instructions which require
FEAT_LSE mandatory from Armv8.1.

Change-Id: I3eb0f29bbccefe6c0f69061aa701187a6364df0c
Signed-off-by: AlexeiFedorov <Alexei.Fedorov@arm.com>
diff --git a/include/lib/spinlock.h b/include/lib/spinlock.h
index 9fd3fc6..055a911 100644
--- a/include/lib/spinlock.h
+++ b/include/lib/spinlock.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013-2018, Arm Limited and Contributors. All rights reserved.
+ * Copyright (c) 2013-2024, Arm Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -15,15 +15,21 @@
 	volatile uint32_t lock;
 } spinlock_t;
 
+typedef struct bitlock {
+	volatile uint8_t lock;
+} bitlock_t;
+
 void spin_lock(spinlock_t *lock);
 void spin_unlock(spinlock_t *lock);
 
+void bit_lock(bitlock_t *lock, uint8_t mask);
+void bit_unlock(bitlock_t *lock, uint8_t mask);
+
 #else
 
 /* Spin lock definitions for use in assembly */
 #define SPINLOCK_ASM_ALIGN	2
 #define SPINLOCK_ASM_SIZE	4
 
-#endif
-
+#endif /* __ASSEMBLER__ */
 #endif /* SPINLOCK_H */