Import AM_ICONV implementation

We *have* to have config.rpath in our own directory, for reasons which
escape me. Usually it would be installed by gettextize or gnulib-tool
but we're not *using* either of those, so just pull in the AM_ICONV bits
manually.

We don't want to ship just config.rpath and *not* the M4 files because
that way we might end up with mismatching versions.

I hate autohell.

(Files taken from Fedora gettext 0.19.2-5.fc21)

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Makefile.am

@@ -221,3 +221,5 @@ po/$(PACKAGE).pot: $(POTFILES) version.sh
 	  --package-name="@PACKAGE@" --package-version="@VERSION@" \
 	  --msgid-bugs-address=openconnect-devel@lists.infradead.org \
 	  -o $@ $(POTFILES)
+
+ACLOCAL_AMFLAGS = -I m4

autogen.sh

@@ -1,6 +1,6 @@
 #!/bin/sh
 
-aclocal && \
+aclocal -I m4 && \
 ${LIBTOOLIZE:-libtoolize} --automake --force && \
 autoheader --force &&
 automake --foreign --add-missing --force && \