scripts: fix download from sourceforge

It seems sourceforge changed yet again the way to download files.
This time, no longer use their 'mesh' thingy, and hard-code the
server to use in the URL... Sigh... :-(

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>
(transplanted from ef6dad58ab1cd38946258552a3ee624a6339f54c)

 # Default test suite configuration

 # Default DejaGnu configuration

 DG_TOOLNAME = gcc

 DG_TARGET_HOSTNAME = 127.0.0.1

 DG_TARGET_USERNAME = root

 # Default tests

 DG_C_TESTS = 

 DG_CPP_TESTS =