update-rc.d: Import newer bbclass from oe-core

* we need this to inhibit update-rc.d when systemd init is selected
* update-rc.d is now only RRECOMMENDed, so can be removed from image

Open-webOS-DCO-1.0-Signed-off-by: Martin Jansa <martin.jansa@lge.com>
Change-Id: Ic7a5388538182bfd23d8f8a561bf92c43df6d8a3
Reviewed-on: https://g2g.palm.com/1845
Reviewed-by: Martin Jansa <Martin.Jansa@lge.com>
Tested-by: Martin Jansa <Martin.Jansa@lge.com>
Reviewed-by: Build Verification
Reviewed-by: Herb Kuta <herb.kuta@lge.com>
Reviewed-by: Susan Montooth <susan.montooth@lge.com>