xilinx_hwicap: make icap_class a static const structure

xilinx_hwicap: make icap_class a static const structure

Now that the driver core allows for struct class to be in read-only
memory, move the icap_class structure to be declared at build time
placing it into read-only memory, instead of having to be dynamically
allocated at load time.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Michal Simek <michal.simek@amd.com>
Cc: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Cc: Ivan Orlov <ivan.orlov0322@gmail.com>
Cc: linux-arm-kernel@lists.infradead.org
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ivan Orlov <ivan.orlov0322@gmail.com>
Link: https://lore.kernel.org/r/20230620143751.578239-17-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>