Create sepolicy for allowing system_server rw in /metadata/repair-mode

Bug: 277561275
Test: ls -all -Z /metadata/repair-mode
Change-Id: Ie27b6ef377bb3503e87fbc5bb2446bc0de396123
diff --git a/private/file_contexts b/private/file_contexts
index 3a9c04d..600c2b8 100644
--- a/private/file_contexts
+++ b/private/file_contexts
@@ -841,6 +841,7 @@
 /metadata/staged-install(/.*)?    u:object_r:staged_install_file:s0
 /metadata/userspacereboot(/.*)?    u:object_r:userspace_reboot_metadata_file:s0
 /metadata/watchdog(/.*)?    u:object_r:watchdog_metadata_file:s0
+/metadata/repair-mode(/.*)?    u:object_r:repair_mode_metadata_file:s0
 
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