After T6508, we need similar changes to GPGME.

For example, I found an issue of gpgme-tool.

Calling gpgme_data_new_from_fd by casting assuanfd_t fd to (int) only works when FD==0|1|2.
Either we need to use _open_osfhandle here (to translate HANDLE into FD) or offer the backend of data-handle.c.

We need to identify issues like this, locate bugs, and fix those bugs.