Allow Developer settings to change runtime size of logd

- permit logd control from system_app

Bug: 14563261
Change-Id: Id5992cca70647a0e4b913a793c6ba8334dc57963

system_app.te

@@ -29,3 +29,5 @@ allow system_app ctl_bugreport_prop:property_service set;
 # Create /data/anr/traces.txt.
 allow system_app anr_data_file:dir ra_dir_perms;
 allow system_app anr_data_file:file create_file_perms;
+
+control_logd(system_app)