cmd/compile: correct wasmexport result type checking
The function resultsToWasmFields was originally for only
wasmimport. I adopted it for wasmexport as well, but forgot to
update a few places that were wasmimport-specific. This leads to
compiler panic if an invalid result type is passed, and also
unsafe.Pointer not actually supported. This CL fixes it.
Updates #65199.
Change-Id: I9bbd7154b70422504994840ff541c39ee596ee8f
Reviewed-on: https://go-review.googlesource.com/c/go/+/611315 Reviewed-by: Michael Knyszek <mknyszek@google.com> Reviewed-by: Achille Roussel <achille.roussel@gmail.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>