caif_virtio: Remove bouncing email addresses

Remove our (soon to be) bouncing email addresses,
and update Dmitri's address.
Dmitry will take over as maintainer for CAIF from now on.

Cc: Vikram Arv <vikram.arv@stericsson.com>
Cc: Dmitry Tarnyagin <dmitry.tarnyagin@stericsson.com>
Cc: Dmitry Tarnyagin <dmitry.tarnyagin@lockless.no>
Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Dmity Tarnyagin <dmitry.tarnyagin@lockless.no>