wifi: iwlwifi: mvm: fix kernel-doc

Fix kernel-doc, adding various documentation, but in some
cases (notably rate scaling) just removing the erroneous
comment format.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20230830112059.4ce1159b51ab.I2021ae335f6b8e50ee2c1c78a79c5eac1c1aa103@changeid


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