package/tcllib: update the upstream URL in Config.in

Update the upstream URL in the help text in Config.in. This
addresses the 'Invalid(Err)' URL status in the package stats
web page output.

Signed-off-by: Mark Corbin <mark@dibsco.co.uk>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
(cherry picked from commit 556fb0d6b6a52abaca508a8b80d79954134bc4b6)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/tcllib/Config.in

@@ -8,4 +8,4 @@ config BR2_PACKAGE_TCLLIB
 	  is to collect commonly used function into a single library,
 	  which users can rely on to be available and stable
 
-	  http://tcl.activestate.com/software/tcllib/
+	  https://www.tcl.tk/software/tcllib/