test: disable large type/stack frame tests for gccgo

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/40370052
diff --git a/test/fixedbugs/bug385_32.go b/test/fixedbugs/bug385_32.go
index 724ed93..4c3cad7 100644
--- a/test/fixedbugs/bug385_32.go
+++ b/test/fixedbugs/bug385_32.go
@@ -9,7 +9,7 @@
 
 package main
 func main() {
-	var arr [1000200030]int   // ERROR "type .* too large"
+	var arr [1000200030]int   // GC_ERROR "type .* too large"
 	arr_bkup := arr
 	_ = arr_bkup
 }