[incremental] allow system server to read /proc/filesystems

Also allow binder service "incremental_service" to be found by service
manager.

Test: boots
BUG: 136132412
Change-Id: I3584a9b69a7e1909f096e3c4579c1834bdfba22e
diff --git a/private/service_contexts b/private/service_contexts
index 7540705..908ff68 100644
--- a/private/service_contexts
+++ b/private/service_contexts
@@ -100,6 +100,7 @@
 ims                                       u:object_r:radio_service:s0
 imms                                      u:object_r:imms_service:s0
 incremental                               u:object_r:incremental_service:s0
+incremental_service                       u:object_r:incremental_service:s0
 ipsec                                     u:object_r:ipsec_service:s0
 ircsmessage                               u:object_r:radio_service:s0
 iris                                      u:object_r:iris_service:s0