security/libssh: Update 0.11.0

• Switch from PORTVERSION to DISTVERSION
• Enable "make test" (disable tests that uses hardcoded paths)
• Clean up and modernize Makefile
• Remove unnecessary CMAKE_ARGS
• Drop (lib)gcrypt support (deprecated upstream)

Changelog: https://gitlab.com/libssh/libssh-mirror/-/tags/libssh-0.11.0

PR: 280720
Approved by: portmgr (maintainer timeout, 2+ weeks)