odhcpd: update to version 2017-02-21

odhcpd: update to version 2017-02-21

1b630f8 router: don't announce prefixes with valid lifetime equal to 0
ba0cac0 router: fix arithmetic exception fault
3495f17 router: allow RA prefix lifetime being set to leasetime value (FS#397)
e437ce9 treewide: simplify dhcp leasetime checking
942fb33 router: support ra_mininterval and ra_lifetime uci parameters (FS#397)
f913337 router.h: fix alignment style
4dc7edb Revert "odhcpd.h: fix alignment style"
62ea54f odhcpd.h: fix alignment style
a898ee5 config: make loglevel configurable via uci (FS#481)
51c756c odhcpd: display correct default log level in usage text
68ee0b5 treewide: define and use macro IN6_IS_ADDR_ULA
fa57225 ndp: deregister netlink event socket for non recoverable errors
ac70d28 odhcpd: fix white space errors

Signed-off-by: Hans Dedecker <dedeckeh@gmail.com>