wifi: zd1211rw: remove __nocast from zd_addr_t

Sparse warns:

drivers/net/wireless/zydas/zd1211rw/zd_usb.c:383:24: warning: implicit cast from nocast type
drivers/net/wireless/zydas/zd1211rw/zd_usb.c:419:24: warning: implicit cast from nocast type

This is an ancient driver which has not have any meaningfuli changes for a long
time and hopefully removed soon. So just remove the __nocast to get rid of the
sparse warnings.

Compile tested only.

Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://msgid.link/20240130151556.2315951-2-kvalo@kernel.org