ath11k: Fix spelling mistake "detetction" -> "detection"

There is a spelling mistake in an ath11k_warn message. Fix it.

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20211123090431.165103-1-colin.i.king@gmail.com