cmd/compile/internal/gc: unexport and make Hasdefer a bool

Passes go build -a -toolexec 'toolstash -cmp' std cmd.

Change-Id: I804ee4252fa9be78cb277faf7f467e6c9cfdd4a6
Reviewed-on: https://go-review.googlesource.com/14319
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
diff --git a/src/cmd/compile/internal/gc/go.go b/src/cmd/compile/internal/gc/go.go
index a6b1ef5..3e7d6aa 100644
--- a/src/cmd/compile/internal/gc/go.go
+++ b/src/cmd/compile/internal/gc/go.go
@@ -616,7 +616,7 @@
 
 var block int32 // current block number
 
-var Hasdefer int // flag that curfn has defer statetment
+var hasdefer bool // flag that curfn has defer statement
 
 var Curfn *Node