etc/dists/scripts/suse-add_ip.sh: remove a warning

When starting a container with no IPs configured, grep spits an error
which should be ignored (it's fine if file doesn't exist):

 # vzctl --verbose --verbose start 1043
 ...
 Running container script: /etc/vz/dists/scripts/suse-add_ip.sh
 grep: /etc/sysconfig/network//ifcfg-venet0: No such file or directory
 ...

We could redirect grep's stderr to /dev/null, but instead let's
add a check that the file exist.

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