package/nfs-utils: bump version to 2.4.3

Bump to version 2.4.3 of nfs-utils.  All patches have been upstreamed, so
drop them all.  It now needs rpcgen built by host-nfs-utils, to do this
let's pass its path to --with-rpcgen= instead of 'internal'.

Signed-off-by: Giulio Benetti <giulio.benetti@benettiengineering.com>
Reviewed-by: Petr Vorel <petr.vorel@gmail.com>
Tested-by: Petr Vorel <petr.vorel@gmail.com>
[Peter: drop AUTORECONF, explicitly depend on host-nfs-utils]
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>