g.mlist: manual fix

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@60540 15284696-431f-4ddb-bdfa-cd5b030d7da7

general/g.mlist/g.mlist.html

@@ -1,7 +1,7 @@
 <h2>DESCRIPTION</h2>
 
 <em>g.mlist</em> searches for data files matching a pattern given by
-wildcards or POSIX Extended Regular Expressions. It is is an extended
+wildcards or POSIX Extended Regular Expressions. It is an extended
 version of <em><a href="g.list.html">g.list</a></em>.
 
 <p>