system_server: allow getprop ro.boot.wificountrycode

avc: denied { read } for pid=505 comm="system_server"
name="u:object_r:wifi_region_prop:s0" dev="tmpfs" ino=5033
scontext=u:r:system_server:s0 tcontext=u:object_r:wifi_region_prop:s0
tclass=file

Bug: 29119219

Change-Id: I92126eb7ce1c6f9877704f6fb6d3abdc707ecd06
diff --git a/sepolicy/system_server.te b/sepolicy/system_server.te
index d854a5b..4176407 100644
--- a/sepolicy/system_server.te
+++ b/sepolicy/system_server.te
@@ -2,3 +2,5 @@
 allow system_server crash_reports_data_file:dir r_dir_perms;
 allow system_server crash_reports_data_file:file r_file_perms;
 allow system_server host1x_device:chr_file rw_file_perms;
+
+get_prop(system_server, wifi_region_prop)