rtlwifi: rtl8821ae: Fix typo in symbol for bandwidth numbers

In several places, "BANDWITH" is used when "BANDWIDTH" should have been
used.

Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Cc: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>