all: fix some staticcheck errors

Updates golang/go#35718

Change-Id: I10bfd5421cd44bb58b8bcaa6e9205040c25f51be
Reviewed-on: https://go-review.googlesource.com/c/tools/+/208257
Run-TryBot: Rebecca Stambler <rstambler@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>
diff --git a/cmd/godex/gccgo.go b/cmd/godex/gccgo.go
index 7644998..a539f98 100644
--- a/cmd/godex/gccgo.go
+++ b/cmd/godex/gccgo.go
@@ -8,11 +8,12 @@
 
 import (
 	"go/importer"
+	"go/token"
 	"go/types"
 )
 
 func init() {
-	register("gccgo", importer.For("gccgo", nil))
+	register("gccgo", importer.ForCompiler(token.NewFileSet(), "gccgo", nil))
 }
 
 // Print the extra gccgo compiler data for this package, if it exists.