make: remove wantToken and skip polling tokenWaitJob

[Simon J Gerraty <sjg%juniper.net@localhost>]

It has been reported from a number of folk that polling tokenWaitJob
adds considerable overhead for very little gain.

I've been testing with this disabled for a while, with no apparent
breakage, and even small jobs show a significant reduction of sys time -
like 50%

The patch I've been using allows enable/disable of polling
(disable by forcing wantToken=0)
but results to date, would support simply ripping it out.

I checked back through the history of wantToken
and it has been there from the initial commit that added the token pipe,
rather than introduced later to address any issue.

If anyone is interested in doing their own testing
the patch is on morden in
~sjg/tmp/d-make-poll-jobq-bool

--sjg