typo: should be OPENSSL_free

Reviewed-by: Richard Levitte <levitte@openssl.org>

ssl/s3_lib.c

@@ -2948,7 +2948,7 @@ void ssl3_clear(SSL *s)
     }
 
     if (s->s3->alpn_selected) {
-        free(s->s3->alpn_selected);
+        OPENSSL_free(s->s3->alpn_selected);
         s->s3->alpn_selected = NULL;
     }