Add sdl3_mutex.odin

vendor/sdl3/sdl3_mutex.odin

@@ -0,0 +1,22 @@
+package sdl3
+
+Mutex  :: struct {}
+RWLock :: struct {}
+
+
+@(default_calling_convention="c", link_prefix="SDL_", require_results)
+foreign lib {
+	CreateMutex             :: proc() -> ^Mutex ---
+	LockMutex               :: proc(mutex: ^Mutex) ---
+	TryLockMutex            :: proc(mutex: ^Mutex) -> bool ---
+	UnlockMutex             :: proc(mutex: ^Mutex) ---
+	DestroyMutex            :: proc(mutex: ^Mutex) ---
+
+	CreateRWLock            :: proc() -> ^RWLock ---
+	LockRWLockForReading    :: proc(rwlock: ^RWLock) ---
+	LockRWLockForWriting    :: proc(rwlock: ^RWLock) ---
+	TryLockRWLockForReading :: proc(rwlock: ^RWLock) -> bool ---
+	TryLockRWLockForWriting :: proc(rwlock: ^RWLock) -> bool ---
+	UnlockRWLock            :: proc(rwlock: ^RWLock) ---
+	DestroyRWLock           :: proc(rwlock: ^RWLock) ---
+}