iwlegacy: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1].

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-throughSigned-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200821063934.GA17838@embeddedor

drivers/net/wireless/intel/iwlegacy/3945-mac.c

@@ -365,7 +365,7 @@ il3945_build_tx_cmd_hwcrypto(struct il_priv *il, struct ieee80211_tx_info *info,
 
 	case WLAN_CIPHER_SUITE_WEP104:
 		tx_cmd->sec_ctl |= TX_CMD_SEC_KEY128;
-		/* fall through */
+		fallthrough;
 	case WLAN_CIPHER_SUITE_WEP40:
 		tx_cmd->sec_ctl |=
 		    TX_CMD_SEC_WEP | (info->control.hw_key->

drivers/net/wireless/intel/iwlegacy/4965-mac.c

@@ -544,7 +544,7 @@ il4965_translate_rx_status(struct il_priv *il, u32 decrypt_in)
 			decrypt_out |= RX_RES_STATUS_BAD_KEY_TTAK;
 			break;
 		}
-		/* fall through - if TTAK OK */
+		fallthrough;	/* if TTAK OK */
 	default:
 		if (!(decrypt_in & RX_MPDU_RES_STATUS_ICV_OK))
 			decrypt_out |= RX_RES_STATUS_BAD_ICV_MIC;
@@ -1617,7 +1617,7 @@ il4965_tx_cmd_build_hwcrypto(struct il_priv *il, struct ieee80211_tx_info *info,
 
 	case WLAN_CIPHER_SUITE_WEP104:
 		tx_cmd->sec_ctl |= TX_CMD_SEC_KEY128;
-		/* fall through */
+		fallthrough;
 	case WLAN_CIPHER_SUITE_WEP40:
 		tx_cmd->sec_ctl |=
 		    (TX_CMD_SEC_WEP | (keyconf->keyidx & TX_CMD_SEC_MSK) <<

drivers/net/wireless/intel/iwlegacy/common.c

@@ -2676,7 +2676,7 @@ il_set_decrypted_flag(struct il_priv *il, struct ieee80211_hdr *hdr,
 		if ((decrypt_res & RX_RES_STATUS_DECRYPT_TYPE_MSK) ==
 		    RX_RES_STATUS_BAD_KEY_TTAK)
 			break;
-		/* fall through */
+		fallthrough;
 
 	case RX_RES_STATUS_SEC_TYPE_WEP:
 		if ((decrypt_res & RX_RES_STATUS_DECRYPT_TYPE_MSK) ==
@@ -2686,7 +2686,7 @@ il_set_decrypted_flag(struct il_priv *il, struct ieee80211_hdr *hdr,
 			D_RX("Packet destroyed\n");
 			return -1;
 		}
-		/* fall through */
+		fallthrough;
 	case RX_RES_STATUS_SEC_TYPE_CCMP:
 		if ((decrypt_res & RX_RES_STATUS_DECRYPT_TYPE_MSK) ==
 		    RX_RES_STATUS_DECRYPT_OK) {