Add module_load permission to system class

Enforce restrictions on kernel module origin when kernel has commit:
61d612ea selinux: restrict kernel module loading

Bug: 27824855
Change-Id: Icf2fefec4231f3df8f0f3d914123c22084d87b0b

access_vectors

@@ -352,6 +352,7 @@ class system
 	syslog_mod
 	syslog_console
 	module_request
+	module_load
 }
 
 #