Fix no-ec2m

Reviewed-by: Paul Yang <yang.yang@baishancloud.com>
(Merged from https://github.com/openssl/openssl/pull/8792)
diff --git a/test/ectest.c b/test/ectest.c
index ab75ace..3f7747e 100644
--- a/test/ectest.c
+++ b/test/ectest.c
@@ -1884,11 +1884,14 @@
      * be the same point on the curve). The add is different for char2 fields.
      */
     type = EC_METHOD_get_field_type(meth);
+#ifndef OPENSSL_NO_EC2M
     if (type == NID_X9_62_characteristic_two_field) {
         /* test for binary curves */
         if (!TEST_true(BN_GF2m_add(x, x, field)))
             goto err;
-    } else if (type == NID_X9_62_prime_field) {
+    } else
+#endif
+    if (type == NID_X9_62_prime_field) {
         /* test for prime curves */
         if (!TEST_true(BN_add(x, x, field)))
             goto err;