powerset: some clean up

* spot/twaalgos/powerset.cc: Remove some unnecessary code, as spotted
by Fanda.  Also fix some comments.
13 jobs for next in 136 minutes and 23 seconds (queued for 2 seconds)
Status Name Job ID Coverage
  Build
passed alpine-gcc #28954

00:22:48

passed arch-clang #28955

00:46:34

passed arch-gcc-glibcxxdebug #28956

00:46:21

passed debian-gcc-snapshot #28953

01:02:56

passed debian-stable-gcc #28951

00:33:52

passed debian-unstable-gcc-coverage #28952

00:47:28

88.8%
passed debpkg-stable #28959

01:57:36

passed debpkg-unstable #28960

02:05:00

passed mingw-shared #28957

00:08:55

passed mingw-static #28958

00:07:27

passed rpm-pkg #28961

00:37:13

 
  Publish
passed publish-rpm #28962
dput

00:00:18

passed publish-unstable #28963
dput

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