[metacity] build: add AC_CONFIG_AUX_DIR

[Alberts Muktupāvels <muktupavels src gnome org>]

commit 5eef1cbba00abdc8698c63fb01fadb8c53dd7740
Author: Alberts Muktupāvels <alberts muktupavels gmail com>
Date:   Sun Sep 20 01:24:47 2015 +0300

    build: add AC_CONFIG_AUX_DIR

 configure.ac |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 8b2aa96..dde451a 100644
--- a/configure.ac
+++ b/configure.ac
@@ -22,6 +22,7 @@ AC_INIT([metacity], [m_version], [m_bugzilla_url])
 AC_CONFIG_HEADERS([config.h])
 AC_CONFIG_SRCDIR([src/core/display.c])
 AC_CONFIG_MACRO_DIR([m4])
+AC_CONFIG_AUX_DIR([build-aux])
 
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