[hitori] build: Use AX_CHECK_ENABLE_DEBUG

[Philip Withnall <pwithnall src gnome org>]

commit 1a99cdb1f21ff7be2312ff623baed4958bff5da6
Author: Philip Withnall <philip withnall collabora co uk>
Date:   Wed Mar 11 12:11:25 2015 +0000

    build: Use AX_CHECK_ENABLE_DEBUG
    
    Drop manual debug code in configure.ac. The --enable-debug option to
    configure remains unchanged. AX_CHECK_ENABLE_DEBUG is automatically
    hooked up to AX_IS_RELEASE, so debug mode will automatically be disabled
    for release builds.
    
    https://wiki.gnome.org/Projects/GnomeCommon/Migration

 configure.ac |    7 +++----
 1 files changed, 3 insertions(+), 4 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 3422927..4077f38 100644
--- a/configure.ac
+++ b/configure.ac
@@ -6,6 +6,9 @@ AC_CONFIG_HEADERS([config.h])
 AC_CONFIG_MACRO_DIR([m4])
 AM_MAINTAINER_MODE([enable])
 
+# Options
+AX_CHECK_ENABLE_DEBUG([yes],[DEBUG])
+
 AC_PROG_CC
 AM_PROG_CC_C_O
 AC_PROG_CPP
@@ -16,10 +19,6 @@ m4_ifdef([AM_SILENT_RULES],[AM_SILENT_RULES([yes])])
 GNOME_COMPILE_WARNINGS([maximum])
 GNOME_MAINTAINER_MODE_DEFINES
 
-# Options
-AC_ARG_ENABLE([debug],AS_HELP_STRING([--enable-debug],[Enable debugging]),[debug=$enableval],[debug=no])
-AM_CONDITIONAL([DEBUG],[test "$debug" = "yes"])
-
 # Code coverage
 AX_CODE_COVERAGE()