Add remount capability to Zygote.

This is a consequence of https://googleplex-android-review.googlesource.com/#/c/278069/

Change-Id: I9b310860534a80e7145950f6c632cf5ba0ad56a7
diff --git a/zygote.te b/zygote.te
index 33e8fe8..3f02293 100644
--- a/zygote.te
+++ b/zygote.te
@@ -37,6 +37,7 @@
 dontaudit zygote self:capability fsetid;
 allow zygote tmpfs:dir { write create add_name setattr mounton search };
 allow zygote tmpfs:filesystem mount;
+allow zygote labeledfs:filesystem remount;
 
 # Handle --invoke-with command when launching Zygote with a wrapper command.
 allow zygote zygote_exec:file { execute_no_trans open };