Remove dumb-allocator code from devel/upload

The 'dumb-allocator' has been removed almost two years ago (commit
6f547f96, “Remove dumb-allocator”), let's remove this special casing
for it from devel/upload.

Signed-off-by: Iustin Pop <iustin@google.com>
Reviewed-by: Helga Velroyen <helgav@google.com>