Add support for tee, splice and vmsplice.

Originally from: vibi sreenivasan <vibi_sreenivasan@cms.com>

Riku: squashed patches together, added a test to configure
and removed compliler warning by picking up correct type for
splice param
Signed-off-by: Nvibisreenivasan <vibi_sreenivasan@cms.com>
Signed-off-by: NRiku Voipio <riku.voipio@iki.fi>