add a dist target for building a dist w/ autoreconf run..

Makefile

@@ -10,4 +10,16 @@ _ggatessh=	ggatessh
 devtest:
 	find [gst]* -type f -name '*.c' -o -name 'Makefile*' -o -name '*.sh' -o -name '*.8' | entr sh -c '(set -o pipefail; make -j 4 | head -n 30) && make install -j 4 && (kyua test -k /usr/tests/Kyuafile sys/geom/class/gate || (cd /usr/tests && kyua report --verbose))'
 
+VERSION!=	git tag --points-at
+dist:
+.if empty(VERSION)
+	@echo 'Failed to find version tag!' && exit 1
+.endif
+	@mkdir ${VERSION}
+	@git archive --prefix ${VERSION}/ ${VERSION} | tar -xf -
+
+	# run autoreconf
+	@cd ${VERSION}/libssh2 && autoreconf -fi
+	@tar -cJf ${VERSION}.tar.xz ${VERSION}
+
 .include <bsd.subdir.mk>