correct export syntax

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@42964 15284696-431f-4ddb-bdfa-cd5b030d7da7

general/g.mkfontcap/g.mkfontcap.html

@@ -34,7 +34,7 @@ use e.g.
 <div class="code"><pre>
 # use local file version instead of system copy
 GRASS_FONT_CAP=$HOME/.gfontcap
-export $GRASS_FONT_CAP
+export GRASS_FONT_CAP
 
 g.mkfontcap
 </pre></div>