[m4-common] Add AX_CHECK_ENABLE_DEBUG and AX_VALGRIND_CHECK macros

[Philip Withnall <pwithnall src gnome org>]

commit f6d169dc026e7214fbee9914aab98519781ddbb0
Author: Philip Withnall <philip withnall collabora co uk>
Date:   Tue Jun 28 17:03:03 2016 +0100

    Add AX_CHECK_ENABLE_DEBUG and AX_VALGRIND_CHECK macros
    
    They are generally useful; AX_CHECK_ENABLE_DEBUG is recommended on the
    gnome-common migration page
    (https://wiki.gnome.org/Projects/GnomeCommon/Migration).

 Makefile.am |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)
---
diff --git a/Makefile.am b/Makefile.am
index 646544c..d049298 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -6,6 +6,7 @@ dist_aclocal_DATA = \
        autoconf-archive/m4/ax_append_link_flags.m4                     \
        autoconf-archive/m4/ax_append_flag.m4                           \
        autoconf-archive/m4/ax_check_compile_flag.m4                    \
+       autoconf-archive/m4/ax_check_enable_debug.m4                    \
        autoconf-archive/m4/ax_check_girs_gjs.m4                        \
        autoconf-archive/m4/ax_check_gir_symbols_gjs.m4                 \
        autoconf-archive/m4/ax_check_link_flag.m4                       \
@@ -20,6 +21,7 @@ dist_aclocal_DATA = \
        autoconf-archive/m4/ax_pkg_check_modules.m4                     \
        autoconf-archive/m4/ax_prog_gjs.m4                              \
        autoconf-archive/m4/ax_require_defined.m4                       \
+       autoconf-archive/m4/ax_valgrind_check.m4                        \
        $(NULL)
 
 all-local: $(dist_aclocal_DATA)