wifi: rtw89: cleanup private data structures

Remove a bunch of unused (and set but unused) fields
from 'struct rtw89_btc_wl_nhm', 'struct rtw89_dle_info',
'struct rtw89_hal' and 'struct rtw89_env_monitor_info'
driver-specific data structures, adjust related bits.

Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
Acked-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20230614081555.91395-1-dmantipov@yandex.ru