[OB] fix typo in NEWS

[Doug Evans]

Checked in as obvious.

Index: NEWS
===================================================================
RCS file: /cvs/src/src/gdb/NEWS,v
retrieving revision 1.279
diff -u -p -r1.279 NEWS
--- NEWS	10 Jul 2008 09:30:57 -0000	1.279
+++ NEWS	10 Jul 2008 16:44:08 -0000
@@ -68,7 +68,7 @@ find [/size-char] [/max-count] start-add
     val1 [, val2, ...]
   Search memory for a sequence of bytes.
 
-set debug timetstamp
+set debug timestamp
 show debug timestamp
   Display timestamps with GDB debugging output.