rapidio: make all 'class' structures const

rapidio: make all 'class' structures const

Now that the driver core allows for struct class to be in read-only
memory, making all 'class' structures to be declared at build time
placing them into read-only memory, instead of having to be dynamically
allocated at load time.

Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ivan Orlov <ivan.orlov0322@gmail.com>
Link: https://lore.kernel.org/r/20230810195103.27069-1-ivan.orlov0322@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>