buildroot

diffutils: bump to version 3.3

Also drop diffutils-gets-no-longer-exists-in-eglibc-2.16.patch because
gets is unconditionally undefined now so we don't need the patch.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>