curlbuild.h.dist: check __LP64__ as well to fix MIPS build

The preprocessor check that sets up the 32bit defines for non-configure
builds didn't work properly for MIPS systems as __mips__ is defined for
both 32bit and 64bit. Now __LP64__ is also checked and indicates 64bit.

Reported-by: Tomas Jakobsson
Fixes #813

include/curl/curlbuild.h.dist

@@ -7,7 +7,7 @@
  *                            | (__| |_| |  _ <| |___
  *                             \___|\___/|_| \_\_____|
  *
- * Copyright (C) 1998 - 2013, Daniel Stenberg, <daniel@haxx.se>, et al.
+ * Copyright (C) 1998 - 2016, Daniel Stenberg, <daniel@haxx.se>, et al.
  *
  * This software is licensed as described in the file COPYING, which
  * you should have received as part of this distribution. The terms
@@ -527,9 +527,9 @@
 /* ===================================== */
 
 #elif defined(__GNUC__)
-#  if defined(__ILP32__) || \
+#  if !defined(__LP64__) && (defined(__ILP32__) || \
       defined(__i386__) || defined(__ppc__) || defined(__arm__) || \
-      defined(__sparc__) || defined(__mips__) || defined(__sh__)
+      defined(__sparc__) || defined(__mips__) || defined(__sh__))
 #    define CURL_SIZEOF_LONG           4
 #    define CURL_TYPEOF_CURL_OFF_T     long long
 #    define CURL_FORMAT_CURL_OFF_T     "lld"