[MacPorts] #29381: add debug variant for tracing support

#29381: add debug variant for tracing support -------------------------------+-------------------------------------------- Reporter: rkitover@… | Owner: macports-tickets@… Type: enhancement | Status: new Priority: Normal | Milestone: Component: ports | Version: 1.9.2 Keywords: | Port: libssh2 -------------------------------+-------------------------------------------- -- Ticket URL: <https://trac.macports.org/ticket/29381> MacPorts <http://www.macports.org/> Ports system for Mac OS