[opentitanlib] Update e2e_bootstrap_rma test to use lc_transition test util.

Nobody has claimed this yet.

### Description

The [`e2e_bootstrap_rma`](https://github.com/lowRISC/opentitan/blob/master/sw/host/tests/rom/e2e_bootstrap_rma/src/main.rs) test performs a lifecycle transition from `PROD` to `RMA`.

Much of its logic is duplicated in the [`lc_transition`](https://github.com/lowRISC/opentitan/blob/master/sw/host/opentitanlib/src/test_utils/lc_transition.rs) opentitanlib test utility. `e2e_bootstrap_rma` can be moved over to using this utility.

There is a caveat that the `e2e_bootstrap_rma` test requires the `RMA_BOOTSTRAP` strapping to be set during the transition, and removed before reset. `lc_transition` includes its own reset, so you will need to remove this strapping yourself and reset again (or wait for the [spin loop](https://github.com/lowRISC/opentitan/blob/master/sw/device/silicon_creator/rom/e2e/BUILD#L458) to time out and reset automatically).

Read sw/host/tests/rom/e2e_bootstrap_rma/src/main.rs alongside sw/host/opentitanlib/src/test_utils/lc_transition.rs, starting with the existing PROD-to-RMA flow and the utility's reset behavior. Done means e2e_bootstrap_rma uses lc_transition while preserving the RMA_BOOTSTRAP strapping requirement and reset sequence; run the relevant e2e_bootstrap_rma test.

Written by the indexing model from the issue text.