test: move unit tests into a sub-menu

The main configuration menu should not contain detail settings.

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/test/Kconfig b/test/Kconfig
index 4650282..6e859fb 100644
--- a/test/Kconfig
+++ b/test/Kconfig
@@ -3,7 +3,9 @@
 	help
 	  See doc/README.POST for more details
 
-menuconfig UNIT_TEST
+menu "Unit tests"
+
+config UNIT_TEST
 	bool "Unit tests"
 	help
 	  Select this to compile in unit tests for various parts of
@@ -107,3 +109,5 @@
 source "test/lib/Kconfig"
 source "test/optee/Kconfig"
 source "test/overlay/Kconfig"
+
+endmenu