tde_create_handbook: Improve build message.

Signed-off-by: Slávek Banko <slavek.banko@axis.cz>

modules/TDEMacros.cmake

@@ -1884,6 +1884,7 @@ macro( tde_create_handbook )
     add_custom_command(
       OUTPUT index.cache.bz2
       COMMAND ${KDE3_MEINPROC_EXECUTABLE} ${_srcdir} --check --cache index.cache.bz2 ${CMAKE_CURRENT_SOURCE_DIR}/index.docbook
+      COMMENT "Generating ${_target}"
       DEPENDS ${_srcs} )
 
     add_custom_target( ${_target} ALL DEPENDS index.cache.bz2 )