zebra: move pbr hash create after update release

zebra: move pbr hash create after update release

Move the pbr hash creation to be after the update release
and dplane install. Now that rules are installed in a separate
dplane pthread, we can have scenarios where we have an interface
flapping and we install/remove rules sufficiently fast enough we
could issue what we think is an update for an identical rule and
end up releasing the rule right after we created it and sent it to
the dplane. This solves the problem of recving duplicate rules
during interface flapping.

Signed-off-by: Stephen Worley <sworley@nvidia.com>