Update AC_PREREQ entries to 2.64

Update AC_PREREQ entries to 2.64

/:
	* configure.ac (AC_PREREQ): Bump to 2.64.

intl/:
	* configure.ac (AC_PREREQ): Bump to 2.64.

libdecnumber/:
	* configure.ac (AC_PREREQ): Bump to 2.64.

libiberty/:
	* configure.ac (AC_PREREQ): Bump to 2.64.

libjava/classpath/:
	* configure.ac (AC_PREREQ): Bump to 2.64.

libjava/:
	* configure.ac (AC_PREREQ): Bump to 2.64.

libjava/libltdl/:
	* configure.ac (AC_PREREQ): Bump to 2.64.  Remove FIXME.

libssp/:
	* configure.ac (AC_PREREQ): Bump to 2.64.

libobjc/:
	* configure.ac (AC_PREREQ): Bump to 2.64.

libstdc++-v3/:
	* configure.ac (AC_PREREQ): Bump to 2.64.

libada/:
	* configure.ac (AC_PREREQ): Bump to 2.64.

libgcc/:
	* configure.ac (AC_PREREQ): Bump to 2.64.

libgfortran/:
	* configure.ac (AC_PREREQ): Bump to 2.64.

boehm-gc/:
	* configure.ac (AC_PREREQ): Bump to 2.64.

gnattools/:
	* configure.ac (AC_PREREQ): Bump to 2.64.

gcc/:
	* configure.ac (AC_PREREQ): Bump to 2.64.

fixincludes/:
	* configure.ac (AC_PREREQ): Bump to 2.64.

libmudflap/:
	* configure.ac (AC_PREREQ): Bump to 2.64.

zlib/:
	* configure.ac (AC_PREREQ): Bump to 2.64.

libffi/:
	* configure.ac (AC_PREREQ): Bump to 2.64.

libcpp/:
	* configure.ac (AC_PREREQ): Bump to 2.64.

libgomp/:
	* configure.ac (AC_PREREQ): Bump to 2.64.

From-SVN: r151059