go.crypto/ssh: import gosshnew.

See https://groups.google.com/d/msg/Golang-nuts/AoVxQ4bB5XQ/i8kpMxdbVlEJ

R=hanwen
CC=golang-codereviews
https://golang.org/cl/86190043

ssh/kex_test.go

@@ -29,7 +29,7 @@ func TestKexes(t *testing.T) {
 			c <- kexResultErr{r, e}
 		}()
 		go func() {
-			r, e := kex.Server(b, rand.Reader, &magics, ecdsaKey)
+			r, e := kex.Server(b, rand.Reader, &magics, testSigners["ecdsa"])
 			s <- kexResultErr{r, e}
 		}()