Fix alim for makefb during tests.
Fix alim for makefb during tests.

The fb was precomputed with alim=2300000, while thereafter it was always
used with alim=1200000.

mancoast/cado-nfs,mancoast/cado-nfs,mancoast/cado-nfs,mancoast/cado-nfs,mancoast/cado-nfs,mancoast/cado-nfs,mancoast/cado-nfs