clean up warnings

libc/sysdeps/linux/common/noophooks.c

@@ -18,9 +18,10 @@
    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
    02111-1307 USA.  */
 
-#include <features.h>
+#include <libc-internal.h>
 
-void __cyg_profile_func_enter (void *this_fn, void *call_site)
+void
+__cyg_profile_func_enter (attribute_unused void *this_fn, attribute_unused void *call_site)
 {
 }
 strong_alias (__cyg_profile_func_enter, __cyg_profile_func_exit)