iwlwifi: remove reference to legacy devices

After driver split, no need to reference to legacy devices, remove comments

Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
diff --git a/drivers/net/wireless/iwlwifi/iwl-dev.h b/drivers/net/wireless/iwlwifi/iwl-dev.h
index 6f6a647..be26145 100644
--- a/drivers/net/wireless/iwlwifi/iwl-dev.h
+++ b/drivers/net/wireless/iwlwifi/iwl-dev.h
@@ -60,11 +60,10 @@
 
 /* Default noise level to report when noise measurement is not available.
  *   This may be because we're:
- *   1)  Not associated (4965, no beacon statistics being sent to driver)
+ *   1)  Not associated  no beacon statistics being sent to driver)
  *   2)  Scanning (noise measurement does not apply to associated channel)
- *   3)  Receiving CCK (3945 delivers noise info only for OFDM frames)
  * Use default noise value of -127 ... this is below the range of measurable
- *   Rx dBm for either 3945 or 4965, so it can indicate "unmeasurable" to user.
+ *   Rx dBm for all agn devices, so it can indicate "unmeasurable" to user.
  *   Also, -127 works better than 0 when averaging frames with/without
  *   noise info (e.g. averaging might be done in app); measured dBm values are
  *   always negative ... using a negative value as the default keeps all