init: wait for ifindex file
init: wait for ifindex file

On s390x a network device creation is triggerd asynchronously by a machine
check interrupt. With this patch init waits until the interface file is
ready to be opened.

Signed-off-by: Peter Morjan <964d0cf54dbf76d367f54f543a3db8d083ad8566@de.ibm.com>

hyperhq/hyperstart,laijs/hyperstart,bergwolf/hyperstart,laijs/hyperstart,bergwolf/hyperstart,gao-feng/hyperstart,hyperhq/hyperstart,gao-feng/hyperstart