dca: make dca_class a static const structure

dca: make dca_class a static const structure

The driver core allows for struct class to be in read-only memory. Move
the dca_class structure to be declared at build time placing it into
read-only memory, instead of having to be dynamically allocated at boot
time.

Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ivan Orlov <ivan.orlov0322@gmail.com>
Link: https://lore.kernel.org/r/20240412151726.189030-1-ivan.orlov0322@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>