bootchart: add policy rules for bootchart

allow the bootchart to create dir and files at init,
also allow user to create the stop and start file under
/data/bootchart directory to start and stop bootchart

Change-Id: Icfee8dcd17366383eef00fbe3139744bf4427a6b
Signed-off-by: Yongqin Liu <yongqin.liu@linaro.org>
diff --git a/file_contexts b/file_contexts
index 04fa4c7..d510476 100644
--- a/file_contexts
+++ b/file_contexts
@@ -227,6 +227,9 @@
 /data/misc/wifi/hostapd(/.*)?   u:object_r:wpa_socket:s0
 /data/misc/zoneinfo(/.*)?       u:object_r:zoneinfo_data_file:s0
 
+# Bootchart data
+/data/bootchart(/.*)?		u:object_r:bootchart_data_file:s0
+
 # coredump directory for userdebug/eng devices
 /cores(/.*)?                    u:object_r:coredump_file:s0