Config.in.legacy: update comment that old entries have been removed

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Cc: Arnout Vandecappelle <arnout@mind.be>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

Config.in.legacy

@@ -135,10 +135,10 @@ comment "legacy options in the menu below. Once you have     "
 comment "disabled all legacy options, this text will         "
 comment "disappear and you will be able to start the build.  "
 comment "*                                                   "
-comment "Note: at some point in the future, the oldest legacy"
-comment "options will be removed, and configuration files    "
-comment "that still have those options set, will fail to     "
-comment "build, or run, in unpredictable ways.               "
+comment "Note: legacy options older than 5 years have been   "
+comment "removed, and configuration files that still have    "
+comment "those options set, will fail to build, or run in    "
+comment "unpredictable ways.                                 "
 comment "----------------------------------------------------"
 endif