Add policy for command line tool to control MTE boot state.

Bug: 206895651

Change-Id: I2e84193668dcdf24bde1c7e12b3cfd8a03954a16
diff --git a/private/file_contexts b/private/file_contexts
index 4a04532..f70c972 100644
--- a/private/file_contexts
+++ b/private/file_contexts
@@ -309,6 +309,7 @@
 /system/bin/lpdumpd        u:object_r:lpdumpd_exec:s0
 /system/bin/rss_hwm_reset	u:object_r:rss_hwm_reset_exec:s0
 /system/bin/perfetto        u:object_r:perfetto_exec:s0
+/system/bin/mtectrl         u:object_r:mtectrl_exec:s0
 /system/bin/traced        u:object_r:traced_exec:s0
 /system/bin/traced_perf        u:object_r:traced_perf_exec:s0
 /system/bin/traced_probes        u:object_r:traced_probes_exec:s0