wifi: mac80211_hwsim: move kernel-doc description

Move the description after the parameter section, to make the
kernel-doc script in verbose mode happy about it.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20230920211508.7f5951a8e327.I5e0cc993acf281d6d90f124c6cce9a2f47000c7d@changeid


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