[earlgrey,epmp] Update ePMP reset config

### Description

In https://github.com/lowRISC/opentitan/pull/28235, ePMP reset config for Darjeeling is updated. Earlgrey should be updated in the same way:
- use auto-generated constants for MMIO range slot
- remove DV_ROM slot. For Earlgrey this also means updating the ROM (removing everything related to slot 13) and deleting `rom_e2e_epmp_init` test which would not be useful anymore

Use PR 28235 as the comparison point, then inspect Earlgrey's ePMP reset configuration and ROM references. Locate the auto-generated MMIO range constants and all references to DV_ROM slot 13, including the rom_e2e_epmp_init test. Done means Earlgrey matches the updated reset configuration and the obsolete ROM and test code are removed.

Written by the indexing model from the issue text.