Since kernel.org is dead, and there is no announced or known estimated
time or return to normality, it is impossible to download any kernel at
this time.
Add a known-working mirror.
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>
1 reporter_name="dsreed on freenode/#crosstool-ng"