wifi: rtlwifi: drop chk_switch_dmdp() from HAL interface

Since there is no chip-specific code behind 'chk_switch_dmdp()',
there is no need to maintain function pointer in 'struct rtl_hal_ops'
and relevant common code may be simplified. Compile tested only.

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/20231016135925.129223-3-dmantipov@yandex.ru