[dev.unified] cmd/compile/internal/walk: fix typo in debug print

We want to print `init` here. We called `ir.TakeInit(r)` earlier, so
`r.Init()` always evaluates to nil at this point.

Change-Id: I196fdcfbf5e63c80b7bff0cce1881c9e58302501
Reviewed-on: https://go-review.googlesource.com/c/go/+/415239
Auto-Submit: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: David Chase <drchase@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>

src/cmd/compile/internal/walk/order.go

@@ -987,7 +987,7 @@ func (o *orderState) stmt(n ir.Node) {
 				do(0, recv.X.Type().Elem())
 				do(1, types.Types[types.TBOOL])
 				if len(init) != 0 {
-					ir.DumpList("ninit", r.Init())
+					ir.DumpList("ninit", init)
 					base.Fatalf("ninit on select recv")
 				}
 				orderBlock(ncas.PtrInit(), o.free)