build: remove workarounds for unsupported gettext versions

Now that we depend on gettext >= 0.19.2 remove the workaround
for issues in autopoint 0.18.3.  Note the scheme currently used in
newer gettext (autopoint) to avoid these issues requires
autoconf >= 2.69, therefore we update this requirement also.

Note the gettext version dependence from gnulib comes from
gnulib using gettext macros, and coreutils indirectly depends on
the gettext module due to:
http://git.sv.gnu.org/gitweb/?p=gnulib.git;a=commitdiff;h=41dca647
bootstrap will then update m4/po.m4 and thus require a
supportng gettext version.

* bootstrap: Remove moot warning (resyncing with gnulib).
* configure.ac (AC_PREREQ): Change to 2.69 (now 3 years old).

bootstrap

@@ -833,21 +833,6 @@ version_controlled_file() {
   fi
 }
 
-# Avoid boostrap failure with gettext/autopoint bug in version 0.18.3.1
-# http://lists.gnu.org/archive/html/coreutils/2013-11/msg00038.html
-# Remove in 2015 when distros have upgraded to >= 0.18.3.2
-autopoint_version=$(get_version $AUTOPOINT)
-# Note autopoint returns version 0.18.3 for version 0.18.3.1
-if test "$autopoint_version" = '0.18.3' ; then
-  if test "$package" = 'coreutils' ; then
-    test -e 'm4/cu-progs.m4' || touch 'm4/cu-progs.m4'
-  fi
-  if ! test -e 'build-aux/git-version-gen' ; then
-    printf "#!/bin/sh\n" > 'build-aux/git-version-gen'
-    chmod a+x 'build-aux/git-version-gen'
-  fi
-fi
-
 # NOTE: we have to be careful to run both autopoint and libtoolize
 # before gnulib-tool, since gnulib-tool is likely to provide newer
 # versions of files "installed" by these two programs.

configure.ac

@@ -18,7 +18,7 @@
 
 dnl Written by Jim Meyering.
 
-AC_PREREQ([2.64])
+AC_PREREQ([2.69])
 
 # Make inter-release version strings look like, e.g., v6.9-219-g58ddd, which
 # indicates that it is built from the 219th delta (in _some_ repository)