ps: respond to loss of that PIDS_WCHAN_ADDR enumerator

No longer will ps print nwchan as 'ffffff', '-' or '1'
since the proc/PID/stat wchan field didn't represent a
real address anyway. Rather, the field will henceforth
output a dash ('-'), the ps customary 'not available'.

That man document was also tweaked to better represent
actual behavior. An asterisk ('*') was never shown for
threaded tasks and that dash ('-') usually didn't mean
running tasks (sometimes associated with permissions).

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

ps/ps.1

@@ -1378,8 +1378,7 @@ T}
 nwchan	WCHAN	T{
 address of the kernel function where the process is sleeping (use
 .B wchan
-if you want the kernel function name).  Running tasks will display a dash
-('\-') in this column.
+if you want the kernel function name).
 T}
 
 ouid	OWNER	T{
@@ -1800,10 +1799,7 @@ mappings are currently excluded; this is subject to change.  (alias
 T}
 
 wchan	WCHAN	T{
-name of the kernel function in which the process is sleeping, a "\-" if the
-process is running, or a "*" if the process is multi\-threaded and
-.B ps
-is not displaying threads.
+name of the kernel function in which the process is sleeping.
 T}
 
 .TE