Our log functions save errno and restore it. Restoring should be
at the very end of the __print_on_level() function, but
commit 6ae4a973 ("rpc: Report back first error message on failure")
messed with it.

Move errno restore at the end of the function.

travis-ci: success for Assorted nitpicks
Signed-off-by: Kir Kolyshkin <kir@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>