autogen.sh: don't update helpers unless there is a newer version
autogen.sh: don't update helpers unless there is a newer version

Updating the autoconf helpers unconditionally is very noisy and
probably the wrong thing to do anyway. Check the version numbers and
only update if the current machine has a newer version installed.

Signed-off-by: H. Peter Anvin (Intel) <8a453bad9912ffe59bc0f0b8abe03df9be19379e@zytor.com>

techkey/nasm,techkey/nasm,techkey/nasm,techkey/nasm,techkey/nasm