top: respond to that preceding fix in the 'select' i/f

top: respond to that preceding fix in the 'select' i/f

This patch makes it possible to honor our '-H' threads
switch even when operating under that '-p' switch used
to select/filter only certain pids. Of course, what we
have done is just exploit the new library enhancement.

[ and we're pretending we don't know the enumerators ]
[ PIDS_FETCH_THREADS_TOO + PIDS_SELECT_PID are equal ]
[ to that PIDS_SELECT_PID_THREADS enumerator itself. ]

[ thankfully, those dependencies can be assured with ]
[ a 'make check-lib' which exploits ITEMTABLE_DEBUG! ]

Signed-off-by: Jim Warner <james.warner@comcast.net>