[tex-k] trivial typo in tex.ch

[Akira Kakuto]

Typo in history of tex.ch (Web2c 7.3.3):

--- tex.ch.save	Tue Mar 21 22:26:08 2000
+++ tex.ch	Mon Apr 30 12:23:46 2001
@@ -12,7 +12,7 @@
 % (12/21/87) ETM Brought up to TeX 2.7
 % (01/14/88) ETM Brought up to TeX 2.9
 % (02/20/88) PAM Revised format and module numbers
-% (03/01/88) ETM Eliminated some unused variables and unnecesary tests
+% (03/01/88) ETM Eliminated some unused variables and unnecessary tests
 % (05/09/88) ETM Added yet another casting bug fix
 % (06/21/88) ETM Brought up to TeX version 2.93
 % (12/11/88) ETM Brought up to TeX version 2.94

-- 
Akira Kakuto