The hijacked load node does not need to be a FIFO. A FIFO is only
required for blocking init's control flow, which is already achieved
by hijacking the enforce node.
Since Android 13, sepolicy are also loaded from APEX modules. Part
of the change is to run restorecon before SELinux is set to enforce.
In order to support this situation, we also hijack plat_file_contexts
if necessary to properly order our operations.
Original idea credits to @yujincheng08, close#5603
