Address lint errors in CV32E40P environment

This pull request address a few more of the SV/UVM lint errors reported by Verissimo. @strichmo, some of this was merged onto the master branch already in PR #840. I'm asking for a PR to cv32e40p/dev because I goofed up on at least one waiver, and I should have been PR'ing to dev all along (my bad).

• mm_ram.sv: The UVM environment no longer uses mm_ram, but the "redundant code" lint error was accurate, so I cleaned that up.
• uvmt_cv32e40p_tb.sv and uvmt_cv32e40p_base_test.sv: removed unused declarations and waived the "do not use $display()" rule (because it does not apply in these cases - see my comments to see if you agree).
• uvma_obi_memory_cov_model, uvma_obi_memory_drv.sv and uvma_obi_memory_seq_item_logger.sv: these are interesting. The linter is flagging redundant code across separate files(!). This is very cool. I put waivers in place for these because much of the redundant code is template generated. @datum-dpoulin, this is something you may want to look at in your templates, but we can live with it for now.