[OE-core] cronie: Convert crontab to a system user

[Richard Purdie]

crontab is meant to be a system user, not a normal user of the system
so lets pass the correct parameters to the system. If we don't do this
it interferes with the setup of normal users, particularly if some 
preset list of users is desired.

Signed-off-by: Richard Purdie <richard.purdie at linuxfoundation.org>
---
diff --git a/meta/recipes-extended/cronie/cronie_1.4.9.bb b/meta/recipes-extended/cronie/cronie_1.4.9.bb
index 7db0381..b338c37 100644
--- a/meta/recipes-extended/cronie/cronie_1.4.9.bb
+++ b/meta/recipes-extended/cronie/cronie_1.4.9.bb
@@ -40,7 +40,7 @@ INITSCRIPT_NAME = "crond"
 INITSCRIPT_PARAMS = "start 90 2 3 4 5 . stop 60 0 1 6 ."
 
 USERADD_PACKAGES = "${PN}"
-GROUPADD_PARAM_${PN} = "crontab"
+GROUPADD_PARAM_${PN} = "--system crontab"
 
 do_install_append () {
 	install -d ${D}${sysconfdir}/sysconfig/