doc: fix godoc build

Author: Stebalien

Makefile

@@ -7,6 +7,7 @@ NPMBIN=./node_modules/.bin
 OUTPUTDIR=public
 PKGDIR=content/reference/pkg
 PORT=1313
+export GO111MODULE=on
 
 ifeq ($(DEBUG), true)
 	PREPEND=

scripts/pkg2md.sh

@@ -44,7 +44,10 @@ case "$name" in
     #
     # TODO also render subdirectories
     export GOPATH="$(pwd)/tmp/gopath"
-    clone "$repo" "$GOPATH/src/$repo" "$ref"
+
+    # Use go-get (without modules)
+    GO111MODULE=off go get "$repo"
+    git -C "$GOPATH/src/$repo" checkout "$ref"
 
     mkdir -p "$basedir/$name"
     # Hugo can't nest pages if there's an `index.md`, so use another name