files: handle errors from fcntl()
files: handle errors from fcntl()

files.c:159:21: error: comparison of unsigned expression < 0 is always
false [-Werror,-Wtautological-compare]
        if (p->fown.signum < 0) {
            ~~~~~~~~~~~~~~ ^ ~

Signed-off-by: Andrey Vagin <74c05afa918858348d6db8037d82fa8124870113@openvz.org>
Signed-off-by: Pavel Emelyanov <c9a32589e048e044184536f7ac71ef92fe82df3e@parallels.com>

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