kernel/linux: add alternate download locations

Some longterm versions are not in the usual directory.
Account for these new locations.

Get rid of the mirror location, now that the main kernel site is
(almost) back to normal operations.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>

# m68k specific configuration file

## depends on EXPERIMENTAL

##

## select ARCH_SUPPORTS_32

## select ARCH_DEFAULT_32

## select ARCH_DEFAULT_BE

## select ARCH_SUPPORTS_WITH_CPU

##

## help The m68k architecture