webos-pro-image: Update layer pins for 2013-09-18

meta-webos as of 2013-09-18 16:52:00 -0700

b2cdc90 webos-image.bbclass: Add luna-service2-disable-security IMAGE_FEATURE
dbdd8f9 webos-image: luna-sysservice=11
6e1b7ae libnih: Use BBCLASSEXTEND and fix sstate signature

Open-webOS-DCO-1.0-Signed-off-by: Susan Montooth <susan.montooth@lge.com>