[foreign-abi] RFR: Add test for vprintf

[Athijegannathan Sundararajan]

On Mon, 15 Jun 2020 11:59:05 GMT, Maurizio Cimadamore <mcimadamore at openjdk.org> wrote:

> For completeness, I added a test for `vprintf` in our `StdLibTest`. The logic is the same as for the `printf` test, but
> instead of passing arguments separately to a specialized handle, we instead construct the correct valist object which
> is then passed to the shared `vprintf` handle.

Marked as reviewed by sundar (Committer).

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PR: https://git.openjdk.java.net/panama-foreign/pull/205