Bumping k8s dependencies to 1.13

vendor/golang.org/x/crypto/bn256/twist.go

@@ -219,10 +219,19 @@ func (c *twistPoint) Mul(a *twistPoint, scalar *big.Int, pool *bnPool) *twistPoi
 	return c
 }
 
+// MakeAffine converts c to affine form and returns c. If c is ∞, then it sets
+// c to 0 : 1 : 0.
 func (c *twistPoint) MakeAffine(pool *bnPool) *twistPoint {
 	if c.z.IsOne() {
 		return c
 	}
+	if c.IsInfinity() {
+		c.x.SetZero()
+		c.y.SetOne()
+		c.z.SetZero()
+		c.t.SetZero()
+		return c
+	}
 
 	zInv := newGFp2(pool).Invert(c.z, pool)
 	t := newGFp2(pool).Mul(c.y, zInv, pool)