ps(1): cleanup

[kib]

Summary

sys/proc.h: add comments to the flag2 bits

ps.1: document rest of flag2 bits

ps.1: visually align process flags hex values by filling leading zeroes

ps(1): clean up after swapout removal

The process flag P_INMEM is always set.  Eliminate all checks for the
bit.  Also eliminate LAZY_PS define and code covered by it: we  do not
have an u-area for long time, and it cannot be swapped out.

Also eliminate setting controlled by the '-f' switch, but accept it for
backward compatibility.

The 'W' process secondary state (swapped out) is impossible, stop
calculating it.

[markj]

bin/ps/ps.1

392

Why keep these flags? P_INMEM is still there but the others are not.

[kib]

Drop P_SWAP* descriptions.