Resolve "[WP] Support for Why-3 1.0"

See merge request frama-c/frama-c!2239

[OCI] revert pkgs.file

See merge request frama-c/frama-c!2245

The function Cvalue.V.cast_int_to_int is unsound here, as conversions to the
_Bool type obey a different rule. This case never happens in the C AST, as
conversions (_Bool)x are translated into (_Bool)(x != 0).

[configure] fix landmarks and document it

See merge request frama-c/frama-c!2227

Change default branch from master to stable/potassium

See merge request frama-c/frama-c!2240