IRQ pin rename + CSR_MIP1 address change

Created by: Silabs-ArjanB

Renamed following pins:

input logic irq_software_i, input logic irq_timer_i, input logic irq_external_i, input logic [47:0] irq_fast_i,

to:

input logic [63:0] irq_i,

Changed CSR_MIP1 address to 0x7D1 (was 0x7D2) to avoid wasting space in the CSR map as MTVECX was removed previously (and to allow for more straight forward future extensions).