Tru64 privsep patch testing

[David Potterveld]

OK, I got a chance to try out the Tru64 patch for privsep. I applied the patch
to 3.4p1. Partial success, in that it now works for me for logins to "root".
Logins to ordinary accounts fail after authentication, when trying to set tty
characteristics. See the excerpt from the debug messages below. This is for
Tru64 V4.0F (with enhanced_security turned on, obviously.) I guess it's time
to dive into the code...

[--- debug transcript ---]
debug1: server_input_channel_req: channel 0 request x11-req reply 0
debug1: session_by_channel: session 0 channel 0
debug1: session_input_channel_req: session 0 req x11-req
debug1: fd 13 setting O_NONBLOCK
debug2: fd 13 is O_NONBLOCK
debug1: channel 1: new [X11 inet listener]
debug1: server_input_channel_req: channel 0 request shell reply 0
debug1: session_by_channel: session 0 channel 0
debug1: session_input_channel_req: session 0 req shell
debug1: fd 4 setting TCP_NODELAY
debug1: channel 0: rfd 12 isatty
debug1: fd 12 setting O_NONBLOCK
debug2: fd 11 is O_NONBLOCK
debug1: Setting controlling tty using TIOCSCTTY.
debug3: : tty /dev/ttyp2 ptyfd 7
debug3:  entering
debug3: : checking request 38
Error in terminal setup.

Couldn't establish session for dhp from xxxx.phy.anl.gov
debug1: Calling cleanup 0x12004fb60(0x140031218)
debug1: session_pty_cleanup: session 0 release /dev/ttyp2
[--- end ---]