cmd/go/internal/modfetch: add newlines to new errors

Change-Id: Id3dafa2381692e3665d6442e558cad7832379ac8
Reviewed-on: https://go-review.googlesource.com/114497
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
diff --git a/vendor/cmd/go/internal/modfetch/convert.go b/vendor/cmd/go/internal/modfetch/convert.go
index 7166bfc..1d7493d 100644
--- a/vendor/cmd/go/internal/modfetch/convert.go
+++ b/vendor/cmd/go/internal/modfetch/convert.go
@@ -51,12 +51,12 @@
 
 		repo, err := Lookup(r.Path)
 		if err != nil {
-			fmt.Fprintf(os.Stderr, "vgo: lookup %s: %v", r.Path, err)
+			fmt.Fprintf(os.Stderr, "vgo: lookup %s: %v\n", r.Path, err)
 			continue
 		}
 		info, err := repo.Stat(r.Version)
 		if err != nil {
-			fmt.Fprintf(os.Stderr, "vgo: stat %s@%s: %v", r.Path, r.Version, err)
+			fmt.Fprintf(os.Stderr, "vgo: stat %s@%s: %v\n", r.Path, r.Version, err)
 			continue
 		}
 		path := repo.ModulePath()