Allow system server to set dynamic ART properties.

This change gives a new type (dalvik_dynamic_config_prop) to some ART
properties such as dalvik.vm.dex2oat-cpu-set and adds a new rule to
allow system server to set them.

Bug: 274530433
Test: Locally added some code to set those properties and saw it being
  successfull.
Change-Id: Ie28602e9039b7647656594ce5c184d29778fa089
diff --git a/private/app.te b/private/app.te
index 5c3472d..1e99cb3 100644
--- a/private/app.te
+++ b/private/app.te
@@ -34,7 +34,7 @@
 get_prop(appdomain, test_harness_prop)
 
 get_prop(appdomain, boot_status_prop)
-get_prop(appdomain, dalvik_config_prop)
+get_prop(appdomain, dalvik_config_prop_type)
 get_prop(appdomain, media_config_prop)
 get_prop(appdomain, packagemanager_config_prop)
 get_prop(appdomain, radio_control_prop)