cw1200: Remove unused function pointer typedef cw1200_wsm_handler

Remove the 'cw1200_wsm_handler' typedef as it is not used.

Signed-off-by: Chen Lin <chen.lin5@zte.com.cn>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/1613446918-4532-1-git-send-email-chen45464546@163.com