Patch taken partially from upstream with some minor refactoring because
the patch from upstream was fairly far off from where this version of
FreeRDP is at.
Built with: Poudriere (11.2 and 13.0-CURRENT)
Tested with: OpenSSL 1.0.2 (11.2, base)
Tested with: OpenSSL 1.1.1 (11.2, security/openssl111)
PR: 233014
Approved by: ultima (ports), myself (maintainer)
MFH: 2018Q4 (OpenSSL build fix)
