Remove parentheses of return.

Since return is inconsistent, I removed unnecessary parentheses and
unified them.

Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/4541)
diff --git a/ssl/ssl_cert.c b/ssl/ssl_cert.c
index 9a1d936..3de3c2c 100644
--- a/ssl/ssl_cert.c
+++ b/ssl/ssl_cert.c
@@ -572,7 +572,7 @@
 
 static int xname_sk_cmp(const X509_NAME *const *a, const X509_NAME *const *b)
 {
-    return (X509_NAME_cmp(*a, *b));
+    return X509_NAME_cmp(*a, *b);
 }
 
 static int xname_cmp(const X509_NAME *a, const X509_NAME *b)
@@ -647,7 +647,7 @@
     lh_X509_NAME_free(name_hash);
     if (ret != NULL)
         ERR_clear_error();
-    return (ret);
+    return ret;
 }
 
 /**