busybox: add comment that other packages are needed

Inspired on the confusion in [1], we want to warn the user that building
without busybox may not lead to a working system.

[1] https://bugs.busybox.net/show_bug.cgi?id=9526

Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/busybox/Config.in

@@ -77,6 +77,9 @@ endif
 
 if !BR2_PACKAGE_BUSYBOX # kconfig doesn't support else
 
+comment "You may need to enable other packages to get a working system"
+comment "You better know what you're doing!"
+
 # This option is not an option of Busybox, it can be selected even if
 # Busybox is not enabled. This dummy option ensures that packages that
 # depend on BR2_PACKAGE_BUSYBOX_SHOW_OTHERS are visible when Busybox