BUG/MEDIUM: tcp: do not skip tracking rules on second pass

The track-sc* tcp rules are bogus. The test to verify if the
tracked counter was already assigned is performed in the same
condition as the test for the action. The effect is that a
rule which tracks a counter that is already being tracked
is implicitly converted to an accept because the default
rule is an accept.

This bug only affects 1.5-dev releases.