Re-add sys_traced prop

Add permissions for:
persist.device_config.global_settings.sys_traced

Bug: b/71737179
Test: As follows:
patch aosp/891475
patch aosp/891853
patch ag/6224352

$ adb shell
walleye:/ $ ps -A | grep traced
nobody        1135     1   52288   2200 0                   0 S traced
nobody        1136     1   52288   2256 0                   0 S
traced_probes
walleye:/ $ settings put global sys_traced 0
walleye:/ $ ps -A | grep traced
1|walleye:/ $
walleye:/ $ settings put global sys_traced 1
1|walleye:/ $ ps -A | grep traced
nobody       12386     1   52288   2208 0                   0 S traced
nobody       12387     1   52288   2248 0                   0 S
traced_probes
Change-Id: I8898672c8fdc9c5d87a31b90f6c7d5c03bef78ed
diff --git a/private/property_contexts b/private/property_contexts
index c1f1228..da09b82 100644
--- a/private/property_contexts
+++ b/private/property_contexts
@@ -184,6 +184,9 @@
 persist.device_config.runtime_native_boot.   u:object_r:device_config_runtime_native_boot_prop:s0
 persist.device_config.media_native.          u:object_r:device_config_media_native_prop:s0
 
+# Properties that relate to legacy server configurable flags
+persist.device_config.global_settings.sys_traced u:object_r:device_config_sys_traced_prop:s0
+
 apexd.                  u:object_r:apexd_prop:s0
 persist.apexd.          u:object_r:apexd_prop:s0