[HW Interface] Command-/SystemInterface export via description. Handles store value instead of pointers

[mamueluth]

This PR should serve as foundation for discussion and is still work in progress. Concept has been tested and works, however there is still some stuff that needs adjustment (tests, some controllers...).

What has been done:

Export of command and state interfaces:

• A description of the command/state interfaces is exported instead of an actual object.
• Default implementation provided for this. Hardware can override if needed.
• No need for user to manage shared memory and pass by raw pointer.
• Set handle values via loans assigned by resource-manager->system->system interface.
• Provide default implementation for import of loans. Hardware can override if needed.
• Default implementation for access of the handle from hardware side.

Handles:

• Handles are adjusted accordingly. Value is now stored directly in handle, not raw pointers are passed around.
• New functionality in Handles which gives user ability to check if read value is: new and valid.

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What needs to be done:

• Adjust some tests

[mergify]

This pull request is in conflict. Could you fix it @mamueluth?

[destogl]

closing in favor of #1240

[destogl]

Obsolete and replaced by #1240