r.stream.segment: manual cosmetics

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@60298 15284696-431f-4ddb-bdfa-cd5b030d7da7

raster/r.stream.segment/r.stream.segment.html

@@ -16,8 +16,8 @@ stream identifiers)  Because streams network produced by <em>r.watershed</em> an
 <em>r.stream.extract</em> may slightly differ in detail, it is required to use both stream
 and direction map produced by the same module. Stream background shall have NULL
 value or zero value. Background values of NULL are by default produced by
-<em>r.watershed</em> and <em>r.stream.extract</em>. If not 0 or NULL use <a
-href="r.mapcalc.html">r.mapcalc</a> to set background values to null.  
+<em>r.watershed</em> and <em>r.stream.extract</em>. If not 0 or NULL use <em><a
+href="r.mapcalc.html">r.mapcalc</a></em> to set background values to null.  
 </dd>
 
 <dt><b>direction</b></dt>