Build - cm: Fix global selinux policy inclusion

We're adding CM-specific policies to an overlay instead of patching
external/sepolicy, so we need to make sure it's included to prevent
misbehaving systems

Change-Id: I3a6b3c5a2d1a16f6e758c446faee3187acc72d36
Signed-off-by: STELIX <ssspinni@gmail.com>
Build - Don't make assumptions about the formats of build descriptions

Change-Id: Id52363d801f39c5f102edfa2a54d991630a31a8e
Signed-off-by: STELIX <ssspinni@gmail.com>