Fix compilation of documentation

Custom footer without date is not needed anymore

doxyfile.in

@@ -792,7 +792,7 @@ HTML_HEADER            =
 # each generated HTML page. If it is left blank doxygen will generate a
 # standard footer.
 
-HTML_FOOTER            = @SRCDIR@/no_date_footer.html
+HTML_FOOTER            =
 
 # The HTML_STYLESHEET tag can be used to specify a user-defined cascading
 # style sheet that is used by each HTML page. It can be used to