Removed test for point equality in ecdsa_verify_digest, point_add() already handles that.

ecdsa.c

@@ -520,13 +520,6 @@ int ecdsa_verify_digest(const uint8_t *pub_key, const uint8_t *sig, const uint8_
 		for (j = 0; j < 30; j++) {
 			if (i == 8 && (s.val[i] >> j) == 0) break;
 			if (s.val[i] & (1u << j)) {
-				bn_mod(&(pub.x), &prime256k1);
-				bn_mod(&(res.x), &prime256k1);
-				if (bn_is_equal(&(pub.x), &(res.x))) {
-					// this is not a failure, but a very inprobable case
-					// that we don't handle because of its inprobability
-					return 4;
-				}
 				point_add(&pub, &res);
 			}
 			point_double(&pub);