iwlwifi: dvm: devices: Fix function documentation formatting issues

iwlwifi: dvm: devices: Fix function documentation formatting issues

Kerneldoc expects attributes/parameters to be in '@*.: ' format and
gets confused if the variable does not follow the type/attribute
definitions.

Fixes the following W=1 kernel build warning(s):

 drivers/net/wireless/intel/iwlwifi/dvm/devices.c:66: warning: Function parameter or member 'priv' not described in 'iwl_beacon_time_mask_low'
 drivers/net/wireless/intel/iwlwifi/dvm/devices.c:66: warning: Function parameter or member 'tsf_bits' not described in 'iwl_beacon_time_mask_low'
 drivers/net/wireless/intel/iwlwifi/dvm/devices.c:77: warning: Function parameter or member 'priv' not described in 'iwl_beacon_time_mask_high'
 drivers/net/wireless/intel/iwlwifi/dvm/devices.c:77: warning: Function parameter or member 'tsf_bits' not described in 'iwl_beacon_time_mask_high'

Cc: Johannes Berg <johannes.berg@intel.com>
Cc: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Cc: Luca Coelho <luciano.coelho@intel.com>
Cc: Intel Linux Wireless <linuxwifi@intel.com>
Cc: Kalle Valo <kvalo@codeaurora.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: linux-wireless@vger.kernel.org
Cc: netdev@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200910065431.657636-15-lee.jones@linaro.org