odhcpd: fix static lease behavior with dhcpv4

git-svn-id: svn://svn.openwrt.org/openwrt/branches/barrier_breaker@42271 3c298f89-4303-0410-b956-a3cf2f4a3e73
Merge branch 'master' into x86_64
Revert "Fix b43 backport patch"

This reverts commit 8bb2bbc5a7d29dbc22cc7af13252cd135671df26.