Clean up code duplication for riscv-dv extensions

Created by: silabs-hfegran

Task Outcome

Clean up corev-dv extensions to prevent duplicate instances of identical code.

Background information

Riscv-dv extensions are implemented both in top level core-v-verif, and in the core-specific env-folders. In some cases, code is copy-pasted between these, where the core-specific variant neither has a unique name nor any changes from code in top level. This leads to confusion and warrants a clean-up.

Location Information

core-v-verif/lib/corev-dv core-v-verif/<core>/env/corev-dv including their respective subfolders

Completion Criteria

Unnecessary duplicate code removed

Additional context

Specific example: The corev_xori_not_instr class exists with an identical name, with identical code in 4 different places in the hierarchy, on top level it is contained in its own specific source file, while in the core-specific locations it belongs to a larger instruction library file that contains several other classes (with several other classes also being duplicated in the same manner). core-v-verif/lib/corev-dv/instr_lib/corev_xori_not_instr.sv core-v-verif/cv32e40p/env/corev-dv/cv32e40p_misc_instr_lib.sv core-v-verif/cv32e40x/env/corev-dv/cv32e40x_misc_instr_lib.sv core-v-verif/cv32e40s/env/corev-dv/cv32e40s_misc_instr_lib.sv