add pass through signals to the `mgmt_core_wrapper`

[passant5]

The following signals are required to pass through the mgmt_core_wrapper:

1. housekeeping/serial_load
2. housekeeping/serial_data_2
3. housekeeping/serial_resetn
4. housekeeping/serial_clock
5. xres_buf/rstb_l
6. simple_por/por_l
7. simple_por/porb_h

To do this, we need 7 input ports <signal_name>_in and 7 output ports <signal_name>_out

[jeffdi]

@passant5 @shalan signal name for housekeeping/serial_load would be serial_load_in and serial_load_out ?

[passant5]

@jeffdi yes

[M0stafaRady]

@jeffdi your last commit added these signals to the mgmt_core only but not the mgmt_core_wrapper module. That broke the RTL simulation because of @passant5 last commit at caravel repo.

[RTimothyEdwards]

FYI, before closing this ticket, I want to mention that #7 is a 3.3V signal and should not have been on the list. This error was corrected later.