read_script(): close fd even if it's 0

Reported by coverity, CID 996832:

> 19. off_by_one: Testing whether handle "fd" is strictly greater than
> zero is suspicious. Did you intend to include equality with zero? "fd"
> leaks when it is zero.

Signed-off-by: Kir Kolyshkin <kir@openvz.org>
1 file changed