mac80211_hwsim: Fix spelling mistake "Droping" -> "Dropping"

There is a spelling mistake in a comment, fix it.

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Link: https://lore.kernel.org/r/20211026094000.209463-1-colin.i.king@gmail.com


Signed-off-by: Johannes Berg <johannes.berg@intel.com>