Use debug-tweaks, allow-root-login to allow root.

root user account is enabled with proper privilege and group,
only if debug-tweaks or allow-root-login FEATURES is defined.
Note: This will not remove root user getting managed from
phosphor-user-manager, instead it will make sure, the privilege
and groups are empty for the root user.

Tested:
1. Verified the default build, which has debug-tweaks, allowing
root user to be with priv-admin, and enabled for all groups.
2. Verified by removing debug-tweaks from the local.conf, and
root user privilege & groups are empty.

Change-Id: Ia93dd82f2b07606e53cabd1bf8a2bc1f5ad3089f
Signed-off-by: Richard Marian Thomaiyar <richard.marian.thomaiyar@linux.intel.com>
diff --git a/conf/distro/include/phosphor-base.inc b/conf/distro/include/phosphor-base.inc
index 20fd216..7970fef 100644
--- a/conf/distro/include/phosphor-base.inc
+++ b/conf/distro/include/phosphor-base.inc
@@ -133,7 +133,7 @@
 KERNEL_FEATURES_append = " phosphor-gpio-keys"
 KERNEL_FEATURES_remove_qemuall = " phosphor-gpio-keys"
 
-IMAGE_CLASSES_append = " image_types_phosphor"
+IMAGE_CLASSES_append = " image_types_phosphor phosphor-rootfs-postcommands"
 IMAGE_CLASSES_append_npcm7xx = " image_types_phosphor_nuvoton"
 
 IMAGE_INSTALL_append = " dbus-broker"