doc: xrdp-sessvc manual page

Add manual page for internally called xrdp-sessvc.

The program should probably be moved to /usr/lib/xrdp/ as it's only
called internally.

docs/man/Makefile.am

@@ -7,7 +7,8 @@ man_MANS = \
   xrdp-keygen.8 \
   xrdp-sesadmin.8 \
   xrdp-sesman.8 \
-  xrdp-sesrun.8
+  xrdp-sesrun.8 \
+  xrdp-sessvc.8
 
 noinst_man_MANS = \
   xrdp-xcon.8

docs/man/xrdp-sessvc.8

@@ -0,0 +1,26 @@
+.TH "xrdp\-sessvc" "8" "0.7.0" "xrdp team" ""
+.SH "NAME"
+xrdp\-sessvc \- \fBxrdp\fR session supervisor
+
+.SH "SYNTAX"
+.B xrdp\-sessman
+.I x_pid wm_pid
+
+.SH "DESCRIPTION"
+\fBxrdp\-sessvc\fR is the \fBxrdp\fR(8) session supervisor, which monitors the running X server and Windows Manager.
+As soon as one of them quits, the other process is terminated as well.
+.br
+This program is only executed internally by \fBxrdp\-sesman\fP(8).
+
+.SH "OPTIONS"
+.TP
+.I x_pid
+The process ID of the forked X server to monitor.
+.TP
+.I wm_pid
+The process ID of the forked Window Manager to monitor.
+
+.SH "SEE ALSO"
+.BR xrdp\-sesrun (8).
+
+for more info on \fBxrdp\fR see http://xrdp.sf.net