sulogin: use bb_error_msg instead of bb_info_msg; better message

Historic "System Maintenance Mode" message is a tiny bit cryptic.
Let's say explicitly what we are doing: we are giving user a shell
(presumably to do some maintenance in single-user mode).

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/loginutils/sulogin.c b/loginutils/sulogin.c
index 33f078a..f324695 100644
--- a/loginutils/sulogin.c
+++ b/loginutils/sulogin.c
@@ -69,17 +69,17 @@
 		);
 		if (r < 0) {
 			/* ^D, ^C, timeout, or read error */
-			bb_info_msg("Normal startup");
+			bb_error_msg("normal startup");
 			return 0;
 		}
 		if (r > 0) {
 			break;
 		}
 		bb_do_delay(LOGIN_FAIL_DELAY);
-		bb_info_msg("Login incorrect");
+		bb_error_msg("Login incorrect");
 	}
 
-	bb_info_msg("System Maintenance Mode");
+	bb_error_msg("starting shell for system maintenance");
 
 	IF_SELINUX(renew_current_security_context());