[Eva] Removes previous mechanism to track garbled mix.

src/kernel_services/abstract_interp/locations.ml

src/kernel_services/abstract_interp/locations.mli

src/kernel_services/abstract_interp/origin.ml

src/kernel_services/abstract_interp/origin.mli

src/plugins/eva/engine/compute_functions.ml

src/plugins/eva/engine/transfer_specification.ml

src/plugins/eva/engine/transfer_stmt.ml

src/plugins/eva/utils/eva_utils.ml

src/plugins/eva/utils/eva_utils.mli