gitcvs-migration: Link to git-cvsimport documentation

Signed-off-by: Frank Lichtenheld <flichtenheld@astaro.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Author: flichtenheld

Documentation/gitcvs-migration.txt

@@ -118,7 +118,7 @@ Importing a CVS archive
 First, install version 2.1 or higher of cvsps from
 link:http://www.cobite.com/cvsps/[http://www.cobite.com/cvsps/] and make
 sure it is in your path.  Then cd to a checked out CVS working directory
-of the project you are interested in and run 'git-cvsimport':
+of the project you are interested in and run linkgit:git-cvsimport[1]:
 
 -------------------------------------------
 $ git cvsimport -C <destination> <module>