Sepolicy changes for system_server to use libvintf

Test: Boot sailfish with shared system image
Bug: 36814984
Change-Id: I2937c20c3b6ca7bf4edab66a74742c48e76c7687

private/file_contexts

@@ -282,6 +282,7 @@
 
 # TODO: b/36790901 move this to /vendor/etc
 /(vendor|system/vendor)/manifest.xml           u:object_r:vendor_configs_file:s0
+/(vendor|system/vendor)/compatibility_matrix.xml u:object_r:vendor_configs_file:s0
 /(vendor|system/vendor)/app(/.*)?              u:object_r:vendor_app_file:s0
 /(vendor|system/vendor)/overlay(/.*)?          u:object_r:vendor_overlay_file:s0
 /(vendor|system/vendor)/framework(/.*)?        u:object_r:vendor_framework_file:s0

private/system_server.te

@@ -86,6 +86,9 @@ allow system_server self:netlink_kobject_uevent_socket create_socket_perms_no_io
 allow system_server self:netlink_socket create_socket_perms_no_ioctl;
 allow system_server self:netlink_generic_socket create_socket_perms_no_ioctl;
 
+# libvintf reads the kernel config to verify vendor interface compatibility.
+allow system_server config_gz:file { read open };
+
 # Use generic "sockets" where the address family is not known
 # to the kernel. The ioctl permission is specifically omitted here, but may
 # be added to device specific policy along with the ioctl commands to be