[gtk+] Drop deprecated autoconf macro

[Matthias Clasen <matthiasc src gnome org>]

commit a03a12098d3b1d4c0eec600af33e6bd82b99eda1
Author: Matthias Clasen <mclasen redhat com>
Date:   Fri Oct 7 13:26:37 2016 -0400

    Drop deprecated autoconf macro
    
    AM_PATH_GTK_3_0 is deprecated, use PKG_CHECK_MODULES([GTK], [gtk+-3.0])
    instead.

 Makefile.am          |    2 +-
 configure.ac         |    1 -
 m4macros/Makefile.am |   10 ---
 m4macros/gtk-3.0.m4  |  217 --------------------------------------------------
 4 files changed, 1 insertions(+), 229 deletions(-)
---
diff --git a/Makefile.am b/Makefile.am
index f2cb7e2..298e4d5 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -2,7 +2,7 @@
 include $(top_srcdir)/Makefile.decl
 
 SRC_SUBDIRS = gdk gtk libgail-util modules demos tests testsuite examples
-SUBDIRS = po po-properties $(SRC_SUBDIRS) docs m4macros build
+SUBDIRS = po po-properties $(SRC_SUBDIRS) docs build
 
 ACLOCAL_AMFLAGS = -I m4 ${ACLOCAL_FLAGS}
 
diff --git a/configure.ac b/configure.ac
index d1df8ec..22aab33 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1895,7 +1895,6 @@ gdk-4.0.pc
 gtk+-4.0.pc
 gtk+-unix-print-4.0.pc
 gail-4.0.pc
-m4macros/Makefile
 po/Makefile.in
 po-properties/Makefile.in
 demos/Makefile