kconfig: qconf: don't show goback button on splitMode

the goback button does nothing on splitMode. So, why display
it?

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
diff --git a/scripts/kconfig/qconf.cc b/scripts/kconfig/qconf.cc
index e43fe4d..6a327b6 100644
--- a/scripts/kconfig/qconf.cc
+++ b/scripts/kconfig/qconf.cc
@@ -437,9 +437,10 @@
 	if (rootEntry != &rootmenu && (mode == singleMode ||
 	    (mode == symbolMode && rootEntry->parent != &rootmenu))) {
 		item = (ConfigItem *)topLevelItem(0);
-		if (!item)
+		if (!item && mode != symbolMode) {
 			item = new ConfigItem(this, 0, true);
-		last = item;
+			last = item;
+		}
 	}
 	if ((mode == singleMode || (mode == symbolMode && !(rootEntry->flags & MENU_ROOT))) &&
 	    rootEntry->sym && rootEntry->prompt) {