Switch from memset_s() -> explicit_bzero().

memset_s() (and all of Annex K) is likely to be removed from the
a future version of the standard.

plugins/sudoers/auth/sudo_auth.c

@@ -326,7 +326,7 @@ verify_user(struct passwd *pw, char *prompt, int validated,
 		break;
 	}
 	if (pass != NULL) {
-	    memset_s(pass, SUDO_CONV_REPL_MAX, 0, strlen(pass));
+	    explicit_bzero(pass, strlen(pass));
 	    free(pass);
 	}