rtlwifi: rtl8723ae: Remove set but not used variables and #defines

radiob_array_table' and 'radiob_arraylen' are not used after setting its value.
It is safe to remove the unused variable. Meanwhile, radio B array should be
removed as well. because it will no longer be referenced.

Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Acked-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>