Fix a potential bug when using __sync_lock_test_and_set()

TYPE __sync_lock_test_and_set (TYPE *ptr, TYPE value, ...)

it is not documented what happens if the two arguments are of different
type like it was before: the first one was lock_word_t (byte) and the
second one was 1 or 0 (int).

Approved by:	Marko (via IRC)

storage/innodb_plugin/include/os0sync.h

@@ -330,7 +330,7 @@ amount of increment. */
 Returns the old value of *ptr, atomically sets *ptr to new_val */
 
 # define os_atomic_test_and_set_byte(ptr, new_val) \
-	__sync_lock_test_and_set(ptr, new_val)
+	__sync_lock_test_and_set(ptr, (byte) new_val)
 
 #elif defined(HAVE_IB_SOLARIS_ATOMICS)