autoconf: Bump version to 2.64.

This release of autoconf brings a number of bug fixes, including a change
to the autoreconf script to pass the correct include path parameter to
aclocal.

Signed-off-by: Will Newton <will.newton@gmail.com>

package/autoconf/autoconf.mk

@@ -3,7 +3,7 @@
 # autoconf
 #
 #############################################################
-AUTOCONF_VERSION = 2.63
+AUTOCONF_VERSION = 2.64
 AUTOCONF_SOURCE = autoconf-$(AUTOCONF_VERSION).tar.bz2
 AUTOCONF_SITE = $(BR2_GNU_MIRROR)/autoconf