Different SM IO capabilities for different roles not supported

As far as I can see there is a global configuration for IO capabilities: ``ble_hs_cfg.sm_io_cap``

I need to support different IO capabilities in different roles, e.g. ``BLE_HS_IO_KEYBOARD_ONLY`` in peripheral role and ``BLE_HS_IO_DISPLAY_ONLY`` in central role. I can work around it by setting the global configuration prior to initiating a central connection, and then setting it back, but that means if in the mean time a peripheral connects to my device it would not work.

Any possibility to set the IO capabilities per role or connection?

Start by tracing the global ble_hs_cfg.sm_io_cap configuration and the uses of BLE_HS_IO_KEYBOARD_ONLY and BLE_HS_IO_DISPLAY_ONLY during central and peripheral setup. Define how capabilities should be selected per role or connection, then verify that simultaneous central and peripheral activity no longer depends on changing the global setting.

Written by the indexing model from the issue text.