[Detail] vendor_init is new introduced in Android P,
and related policies have not been created yet.
[Solution] Add policies for vendor_init
MTK-Commit-Id: 00dc11bf94cbb7909ef58482d7726ebe8b954782
Change-Id: Ic2286e8e3e67b4005c7e2df18d217275f069f208
CR-Id: ALPS03881723
Feature: [Android Default] SELinux, SEAndroid, and SE-MTK