ruby: remove prebuilt kernel reference

Change-Id: I9d7e05e55b18155dd2fcf5a99f34385c0566c0d9
ruby: remove custom libril

Change-Id: Ida3661f275a2a06f865c09449ad7f544e5a6e62e
ruby: update for 4.4 sdcard

Change-Id: Idca420be29c8a9c45d03a476d6ec5dd86b7ccfc1