busybox: fix: ip addr flush hangs when run by non-root user

busybox: fix: ip addr flush hangs when run by non-root user

Add upstream patch from:
https://git.busybox.net/busybox/commit/?id=028c5aa18b5273c029f0278232d922ee1a164de6

The patch fixes a problem with an infinite loop causing 100% CPU usage
when running the following command /lib/preinit/10_indicate_preinit
without the CAP_NET_ADMIN capability (such as in Docker):
  ip -4 address flush dev $pi_ifname

Signed-off-by: Mikael Magnusson <[email protected]>
Signed-off-by: Hans Dedecker <[email protected]> [refresh patch]