[guest] Add vsock service to guest

Test: run-test guest_integration_tests

Change-Id: I44e368383e57c779e342d6c0775d31b0fbbeebee

images/guest/BUILD.gn

diff --git a/images/guest/BUILD.gn b/images/guest/BUILD.gn
index c5bc4cf..7cb254c 100644
--- a/images/guest/BUILD.gn
+++ b/images/guest/BUILD.gn
@@ -17,6 +17,7 @@
   get_label_info("//garnet/bin/run", "label_no_toolchain"),
   get_label_info("//garnet/bin/sysmgr", "label_no_toolchain"),
   get_label_info("//garnet/bin/trace", "label_no_toolchain"),
+  get_label_info("//garnet/bin/vsock_service:vsock_service", "label_no_toolchain"),
   get_label_info("//garnet/go/src/pmd:pkgsvr", "label_no_toolchain"),
 ]