runtime: remove unnecessary functions calling between C and Go

These functions were needed during the transition of the runtime from
C to Go, but are no longer necessary.

Change-Id: I6aed93b624e02be9bbcf212e07fc2638e94476ad
Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/179879
Reviewed-by: Cherry Zhang <cherryyz@google.com>
5 files changed