iwlwifi: avoid device type checking in generic code

Avoid checking for specified device type to perform certain function,
switch to .cfg approach as more generic and better implementation
method.

Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
diff --git a/drivers/net/wireless/iwlwifi/iwl-scan.c b/drivers/net/wireless/iwlwifi/iwl-scan.c
index 1544d75..5ecfc7f 100644
--- a/drivers/net/wireless/iwlwifi/iwl-scan.c
+++ b/drivers/net/wireless/iwlwifi/iwl-scan.c
@@ -830,10 +830,11 @@
 		 */
 		scan->good_CRC_th = is_active ? IWL_GOOD_CRC_TH : 0;
 
-		/* Force use of chains B and C (0x6) for scan Rx for 4965
-		 * Avoid A (0x1) because of its off-channel reception on A-band.
+		/* Force use of chains B and C (0x6) for scan Rx
+		 * Avoid A (0x1) for the device has off-channel reception
+		 * on A-band.
 		 */
-		if ((priv->hw_rev & CSR_HW_REV_TYPE_MSK) == CSR_HW_REV_TYPE_4965)
+		if (priv->cfg->off_channel_workaround)
 			rx_ant = ANT_BC;
 	} else {
 		IWL_WARN(priv, "Invalid scan band count\n");