net: fix socket send/receive timeout

Microsecond values were passed as is instead of being scaled by hz.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>
tst-kill: fix timeout test

The timeout test sets a 2 second timeout and a 1 second alarm, and expects
the timeout to happen first.

Change the timeout to 0.5 seconds.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>