fix missing PD

Reference: /n/atom/patch/applied2013/wspdnit
Date: Wed Jun 26 05:06:25 CES 2013
Signed-off-by: quanstro@quanstro.net

--- /sys/man/3/ws	Wed Jun 26 05:06:21 2013
+++ /sys/man/3/ws	Wed Jun 26 05:06:22 2013
@@ -42,6 +42,7 @@
 .B ctl
 file takes the following commands:
 .TF "\fBstartxx
+.PD
 .TP
 .B start
 start data collection,
@@ -51,7 +52,6 @@
 .TP
 .B clear
 forget collected data.
-
 .PP
 The
 .B data