llvm: Update from latest meta-oe

:Release Notes:
Import fixes and improved packaging from latest meta-oe.

:Detailed Notes:
Take advantage of changes from this patchset
http://lists.openembedded.org/pipermail/openembedded-devel/2013-July/091310.html
and fix undeterministicly enabled zlib dependency

:Testing Performed:
Tested in VirtualBox

:QA Notes:

:Issues Addressed:
[GF-9365]  Explicitly enable or disable autodetected dependencies
[GF-35765] Update mesa and llvm in meta-webos-backports from latest
           oe-core and meta-oe

Open-webOS-DCO-1.0-Signed-off-by: Martin Jansa <martin.jansa@lge.com>
Change-Id: I199ab2aa9c45d80938a7f9de5cd9470356adfa6f
Reviewed-on: https://g2g.palm.com/2899
Reviewed-by: Build Verification
Reviewed-by: Martin Jansa <Martin.Jansa@lge.com>
Tested-by: Martin Jansa <Martin.Jansa@lge.com>
Reviewed-by: Susan Montooth <susan.montooth@lge.com>