[master] 465b8b8 Fix sourcing of varnish.m4 when building on FreeBSD

[Dridi Boukelmoune]

commit 465b8b8cde4510c409ce98578ed396fda3f3ccd7
Author: Mark Felder <feld at FreeBSd.org>
Date:   Mon Aug 7 19:16:42 2017 -0500

    Fix sourcing of varnish.m4 when building on FreeBSD

diff --git a/Makefile.am b/Makefile.am
index f018bc8..006c770 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -1,4 +1,4 @@
-ACLOCAL_AMFLAGS = -I m4
+ACLOCAL_AMFLAGS = -I m4 -I .
 
 SUBDIRS = include lib bin etc doc man