[gnome-directory-thumbnailer] build: Update ACLOCAL flags

[Philip Withnall <pwithnall src gnome org>]

commit 735fbb14b601f2342dec5c4398d9bfc6b09696c3
Author: Philip Withnall <philip withnall collabora co uk>
Date:   Tue Jun 9 13:31:27 2015 +0100

    build: Update ACLOCAL flags

 Makefile.am  |    2 +-
 configure.ac |    5 -----
 2 files changed, 1 insertions(+), 6 deletions(-)
---
diff --git a/Makefile.am b/Makefile.am
index 1800f0c..27a886a 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -1,4 +1,4 @@
-ACLOCAL_AMFLAGS = -I m4 ${ACLOCAL_FLAGS}
+ACLOCAL_AMFLAGS = --install -I m4 ${ACLOCAL_FLAGS}
 SUBDIRS = . po
 
 DISTCHECK_CONFIGURE_FLAGS =
diff --git a/configure.ac b/configure.ac
index 450e94c..3a460bb 100644
--- a/configure.ac
+++ b/configure.ac
@@ -51,11 +51,6 @@ GNOME_COMPILE_WARNINGS([maximum])
 GNOME_MAINTAINER_MODE_DEFINES
 AX_GENERATE_CHANGELOG
 
-AC_SUBST([AM_CPPFLAGS])
-AC_SUBST([AM_CFLAGS])
-AC_SUBST([AM_CXXFLAGS])
-AC_SUBST([AM_LDFLAGS])
-
 AC_CONFIG_FILES([
 Makefile
 po/Makefile.in