Allow dumpstate and shell to list services.

Addresses the following denials:
avc:  denied  { list } for service=NULL scontext=u:r:shell:s0 tcontext=u:r:servicemanager:s0 tclass=service_manager
avc:  denied  { list } for service=NULL scontext=u:r:dumpstate:s0 tcontext=u:r:servicemanager:s0 tclass=service_manager

Bug: 18864737
Change-Id: I72bd2cd9663f1df9410c2139411038fa997bf1b4

dumpstate.te

@@ -118,3 +118,5 @@ allow dumpstate {
     system_app_service
     system_server_service
 }:service_manager find;
+
+allow dumpstate servicemanager:service_manager list;

shell.te

@@ -55,3 +55,6 @@ allow shell debugfs:file r_file_perms;
 
 # allow shell to run dmesg
 allow shell kernel:system syslog_read;
+
+# allow shell to list services
+allow shell servicemanager:service_manager list;