tools: hv: Check return value of setsockopt call

Check return value of setsockopt call and if it fails print error to the
system log and exit with non-zero value.

Signed-off-by: Tomas Hozza <thozza@redhat.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>