sepolicy: move init scripts to vendor and define selinux domain

Moving  following init scripts to vendor and add a selinux domain
for each.

label init.qcom.early_boot.sh and add rules for init to run it
Add policy for init.qcom.post_boot service
Add policy for init.qcom service
Add policy for init.class_main service
Add policy for init.qcom.usb service
Add policy for init.qcom.sensors service
Add policy for init.qcom.bt.sh service
Add policy for init.qcom.class_core.sh service

Change-Id: Ib94c563c9b10c4aee5ead24feb431216ed337aa7