change return (x) to return x

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3878)
diff --git a/crypto/mem_dbg.c b/crypto/mem_dbg.c
index c0bb2be..1ab52a8 100644
--- a/crypto/mem_dbg.c
+++ b/crypto/mem_dbg.c
@@ -1,5 +1,5 @@
 /*
- * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright 1995-2017 The OpenSSL Project Authors. All Rights Reserved.
  *
  * Licensed under the OpenSSL license (the "License").  You may not use
  * this file except in compliance with the License.  You can obtain a copy
@@ -183,7 +183,7 @@
         break;
     }
     CRYPTO_THREAD_unlock(malloc_lock);
-    return (ret);
+    return ret;
 #endif
 }
 
@@ -206,7 +206,7 @@
 
         CRYPTO_THREAD_unlock(malloc_lock);
     }
-    return (ret);
+    return ret;
 }
 
 static int mem_cmp(const MEM *a, const MEM *b)
@@ -231,7 +231,7 @@
     ret = (size_t)a->addr;
 
     ret = ret * 17851 + (ret >> 14) * 7 + (ret >> 4) * 251;
-    return (ret);
+    return ret;
 }
 
 /* returns 1 if there was an info to pop, 0 if the stack was empty. */
@@ -292,7 +292,7 @@
         CRYPTO_mem_ctrl(CRYPTO_MEM_CHECK_ENABLE);
     }
 
-    return (ret);
+    return ret;
 }
 
 int CRYPTO_mem_debug_pop(void)
@@ -304,7 +304,7 @@
         ret = pop_info();
         CRYPTO_mem_ctrl(CRYPTO_MEM_CHECK_ENABLE);
     }
-    return (ret);
+    return ret;
 }
 
 static unsigned long break_order_num = 0;