postcreate.sh: check if file exists before setting fattr

From the bug reporter:

	template does not have /usr/sbin/suexec inside.

	[root@backup01-va]# vzctl create 6546
	...
	Creating container private area (fedora-minimal-15-x86)
	Performing postcreate actions
	setfattr: /vz/root/6546/usr/sbin/suexec: No such file or directory
	CT configuration saved to /etc/vz/conf/6546.conf
	Container private area was created

http://bugzilla.openvz.org/2363

Reported-by: Barmaley <barmaley@knownhost.com>
Signed-off-by: Kir Kolyshkin <kir@openvz.org>
1 file changed