Sepolicy: Move otapreopt_chroot to private

Move complete domain to private/. Move referencing parts in domain
and kernel to private.

Bug: 128840749
Test: m
Change-Id: I5572c3b04e41141c8f4db62b1361e2b392a5e2da
diff --git a/private/kernel.te b/private/kernel.te
index a4e6ebe..207800e 100644
--- a/private/kernel.te
+++ b/private/kernel.te
@@ -1,3 +1,8 @@
 typeattribute kernel coredomain;
 
 domain_auto_trans(kernel, init_exec, init)
+
+# Allow the kernel to read otapreopt_chroot's file descriptors and files under
+# /postinstall, as it uses apexd logic to mount APEX packages in /postinstall/apex.
+allow kernel otapreopt_chroot:fd use;
+allow kernel postinstall_file:file read;