sysvinit: depend on SysV selected as init system.

In order to prevent sysvinit and systemd to be selected at the same
time, sysvinit can now only be selected if SysV is chosen as init
system.

Signed-off-by: Eric Le Bihan <eric.le.bihan.dev@free.fr>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/sysvinit/Config.in

@@ -1,5 +1,6 @@
 config BR2_PACKAGE_SYSVINIT
 	bool "sysvinit"
+	depends on BR2_INIT_SYSV
 	help
 	  /sbin/init - parent of all processes