Add appcompat override files and contexts to SELinux

This also allows the zygote to bind mount the system properties

Bug: 291814949
Test: manual
Change-Id: Ie5540faaf3508bc2d244c952904838d56aa67434
diff --git a/private/file_contexts b/private/file_contexts
index 2d9b30d..2481c07 100644
--- a/private/file_contexts
+++ b/private/file_contexts
@@ -200,7 +200,9 @@
 /dev/xt_qtaguid	u:object_r:qtaguid_device:s0
 /dev/zero		u:object_r:zero_device:s0
 /dev/__properties__ u:object_r:properties_device:s0
+/dev/__properties__/appcompat_override u:object_r:properties_device:s0
 /dev/__properties__/property_info   u:object_r:property_info:s0
+/dev/__properties__/appcompat_override/property_info   u:object_r:property_info:s0
 #############################
 # Linker configuration
 #