imp: allow cgo while disabling libwasmvm linking (backport #527)

[mergify]

As discussed via comms channels.

• Adds the ability to enable cgo but disable libwasmvm in binary compliation.

I will test this for the usecase mentioned with ibc 08-wasm before publishing the PR as ready for review.
This is the associated PR on ibc-go: cosmos/ibc-go#5923

And please let me know if I am missing something! 🖤

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This is an automatic backport of pull request #527 done by Mergify.

[mergify]

Cherry-pick of bcde382 has failed:

On branch mergify/bp/release/2.0/pr-527
Your branch is ahead of 'origin/release/2.0' by 5 commits.
  (use "git push" to publish your local commits)

You are currently cherry-picking commit bcde382.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Changes to be committed:
	modified:   lib.go
	new file:   lib_libwasmvm.go
	new file:   lib_libwasmvm_test.go
	deleted:    lib_no_cgo.go
	modified:   lib_test.go

Unmerged paths:
  (use "git add/rm <file>..." as appropriate to mark resolution)
	deleted by them: lib_no_cgo_test.go

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally