crypto/elliptic: fix BenchmarkMarshalUnmarshal/Compressed

Change-Id: Ifbf4a95e5f315a88633ec0170625cadb087167c0
Reviewed-on: https://go-review.googlesource.com/c/go/+/396934
Run-TryBot: Filippo Valsorda <[email protected]>
Trust: Filippo Valsorda <[email protected]>
TryBot-Result: Gopher Robot <[email protected]>
Reviewed-by: Roland Shoemaker <[email protected]>

Author: FiloSottile

src/crypto/elliptic/elliptic_test.go

@@ -364,8 +364,8 @@ func BenchmarkMarshalUnmarshal(b *testing.B) {
 		b.Run("Compressed", func(b *testing.B) {
 			b.ReportAllocs()
 			for i := 0; i < b.N; i++ {
-				buf := Marshal(curve, x, y)
-				xx, yy := Unmarshal(curve, buf)
+				buf := MarshalCompressed(curve, x, y)
+				xx, yy := UnmarshalCompressed(curve, buf)
 				if xx.Cmp(x) != 0 || yy.Cmp(y) != 0 {
 					b.Error("Unmarshal output different from Marshal input")
 				}