fixed unicode usage.

Reference: /n/sources/patch/applied/unicode-man
Date: Wed Apr 19 20:44:28 CES 2006
Signed-off-by: arvindht@gmail.com

--- /sys/man/1/ascii	Wed Apr 19 20:43:55 2006
+++ /sys/man/1/ascii	Wed Apr 19 20:43:47 2006
@@ -17,9 +17,6 @@
 ]
 .PP
 .B unicode
-[
-.B -nt
-]
 .IB hexmin - hexmax
 .PP
 .B unicode