Expose IKE module API: IKE ID, TS and SaProposal

This commit updates system-current to expose APIs of IKE mainline
module. Changes include:
- Feed IKE API source file to base/Android.bp
- Update system-current.txt to expose IkeIdentification,
  IkeTrafficSelector and SaProposal

Bug: 143983419
Test: make update-api && make
Change-Id: I3826434850de7b264ab44d46ca0bd82359dc98fe
diff --git a/Android.bp b/Android.bp
index 284e701..28ced18 100644
--- a/Android.bp
+++ b/Android.bp
@@ -1068,6 +1068,7 @@
         ":core-current-stubs-source",
         ":core_public_api_files",
         ":updatable-media-srcs",
+        ":ike-api-srcs",
     ],
     libs: ["framework-internal-utils"],
     local_sourcepaths: frameworks_base_subdirs,