fix ares_threadsafety() prototype

include/ares.h

@@ -745,7 +745,7 @@ CARES_EXTERN int         ares_inet_pton(int af, const char *src, void *dst);
  *
  *  \return ARES_TRUE if built with threadsafety, ARES_FALSE if not
  */
-CARES_EXTERN ares_status_t ares_threadsafety(void);
+CARES_EXTERN ares_bool_t ares_threadsafety(void);
 
 #ifdef __cplusplus
 }

src/lib/ares__threads.c

@@ -149,7 +149,7 @@ void ares__channel_unlock(ares_channel_t *channel)
   ares__thread_mutex_unlock(channel->lock);
 }
 
-ares_status_t ares_threadsafety(void)
+ares_bool_t ares_threadsafety(void)
 {
   return ARES_TRUE;
 }
@@ -177,7 +177,7 @@ void ares__channel_unlock(ares_channel_t *channel)
   (void)channel;
 }
 
-ares_status_t ares_threadsafety(void)
+ares_bool_t ares_threadsafety(void)
 {
   return ARES_FALSE;
 }