Add GEOS wrapper for `GEOSCoverageSimplifyVW_r`

[peterstace]

Description

See doc comment in geos/entrypoints.go for what the function does.

Check List

Have you:

• Added unit tests? Yes.

• Add cmprefimpl tests? (if appropriate?) N/A.

• Updated release notes? (if appropriate?) Yes.

Related Issue

• N/A

[peterstace]

Thanks Albert!