wifi: rtw88: remove unsupported interface type of mesh point

Mesh point was added during development, but not remove at first
submission, so it should not work properly. Remove it to reflect correct
supported features.

Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Link: https://msgid.link/20240329114403.5539-1-pkshih@realtek.com