cfg80211: fix an htmldoc warning

cfg80211: fix an htmldoc warning

The htmldoc produces this warning which was introduced
bu the commit below.

include/net/cfg80211.h:6643: warning: expecting prototype for wiphy_rfkill_set_hw_state().
Prototype was for wiphy_rfkill_set_hw_state_reason() instead

Fixes: 6f779a66dc84 ("cfg80211: allow specifying a reason for hw_rfkill")
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Link: https://lore.kernel.org/r/20210413113850.59098-1-emmanuel.grumbach@intel.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>