hush: enable "msh is deprecated" message in msh stub

After giving a few more years for everyone to notice and migrate,
can nuke all remains of msh.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/shell/hush.c b/shell/hush.c
index b9dd84f..3c4621f 100644
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -8533,7 +8533,7 @@
 int msh_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int msh_main(int argc, char **argv)
 {
-	//bb_error_msg("msh is deprecated, please use hush instead");
+	bb_error_msg("msh is deprecated, please use hush instead");
 	return hush_main(argc, argv);
 }
 #endif