DPC writes treated differently based on PULP_SECURE parameter

Created by: Silabs-ArjanB

The code for DPC writes are slightly different based on the PULP_SECURE parameter. This type of typo's likely derive from the high amount of code duplication in riscv_cs_registers.sv.

PULP_SECURE==1 section:

  CSR_DPC:
           if (csr_we_int)
           begin
                depc_n = csr_wdata_int & ~32'b1; // force 16-bit alignment
           end

PULP_SECURE == 0 section:

  CSR_DPC:
           if (csr_we_int)
           begin
                depc_n = csr_wdata_int;
           end

Is it maybe an idea to restructure riscv_cs_registers.sv such that the duplicate code is avoided (and parameters are used inside the expressions in the read/write logic case statements to achieve the same effect as is now achieved with generate statements)?