Minor updates to readline configury

Christian's recent patches to gnulib made me realize that readline
should be changed to use AC_CONFIG_MACRO_DIRS (ACLOCAL_AMFLAGS is
deprecated) and that it can put the automake options into
configure.ac.  I also added no-define to the automake options.  This
doesn't matter much (we don't generate a config.h here), but gnulib
does it, and it does make configure slightly smaller.

readline/ChangeLog
2019-11-15  Tom Tromey  <tromey@adacore.com>

	* configure, Makefile.in: Rebuild.
	* configure.ac: Use AC_CONFIG_MACRO_DIRS.  Pass options to
	AM_INIT_AUTOMAKE.
	* Makefile.am (AUTOMAKE_OPTIONS, ACLOCAL_AMFLAGS): Remove.

Change-Id: If421599cc9dd9c4c3c37b9b439ab2c22c01742ed