attach: don't ignore sigint/sigkill if stdin is redirected
attach: don't ignore sigint/sigkill if stdin is redirected

If attach is being done over passed-in fds, then we shouldn't
mess with the caller's signal table to ignore ctrl-c over the
fd.

Signed-off-by: Serge Hallyn <3df611b026e4639bee8aef7a4beb2e39fcebb313@ubuntu.com>
Acked-by: Stéphane Graber <089afc6d81f66f1168a9849e15660feae286e024@ubuntu.com>

ojkastl/lxc_Patches,ojkastl/lxc_Patches,ojkastl/lxc_Patches,ojkastl/lxc_Patches