ice: replace "fallthrough" comments with fallthrough reserved word

"fallthrough" comments are used in switch case statements to explicitly
indicate the code is intended to fall through to the following statement.
Different variants of "fallthough" are acceptable, e.g. "fall through",
"fallthrough", "Fall-through".  The GCC compiler has an optional warning
(-Wimplicit-fallthrough[=n]) to warn when such a comment is not present;
the default version of which is enabled when compiling the Linux kernel.

There have been recent discussions in kernel mailing lists regarding
replacing non-standardized "fallthrough" comments with the pseudo-reserved
word 'fallthrough' which will be defined as __attribute__ ((fallthrough))
for versions of gcc that support it (i.e. gcc 7 and newer) or as a nop
for versions that do not.  Replace "fallthrough" comments with fallthrough
reserved word.
Signed-off-by: Bruce Allan <bruce.w.allan@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/ice/ice_common.c

@@ -1181,7 +1181,7 @@ ice_aq_send_cmd(struct ice_hw *hw, struct ice_aq_desc *desc, void *buf,
 	case ice_aqc_opc_release_res:
 		if (le16_to_cpu(cmd->res_id) == ICE_AQC_RES_ID_GLBL_LOCK)
 			break;
-		/* fall-through */
+		fallthrough;
 	default:
 		mutex_lock(&ice_global_cfg_lock_sw);
 		lock_acquired = true;
@@ -2703,7 +2703,7 @@ __ice_aq_get_set_rss_lut(struct ice_hw *hw, u16 vsi_id, u8 lut_type, u8 *lut,
 				 ICE_AQC_GSET_RSS_LUT_TABLE_SIZE_M;
 			break;
 		}
-		/* fall-through */
+		fallthrough;
 	default:
 		status = ICE_ERR_PARAM;
 		goto ice_aq_get_set_rss_lut_exit;

drivers/net/ethernet/intel/ice/ice_main.c

@@ -2985,7 +2985,7 @@ ice_log_pkg_init(struct ice_hw *hw, enum ice_status *status)
 		default:
 			break;
 		}
-		/* fall-through */
+		fallthrough;
 	default:
 		dev_err(dev, "An unknown error (%d) occurred when loading the DDP package.  Entering Safe Mode.\n",
 			*status);

drivers/net/ethernet/intel/ice/ice_switch.c

@@ -760,7 +760,7 @@ ice_fill_sw_rule(struct ice_hw *hw, struct ice_fltr_info *f_info,
 		break;
 	case ICE_SW_LKUP_ETHERTYPE_MAC:
 		daddr = f_info->l_data.ethertype_mac.mac_addr;
-		/* fall-through */
+		fallthrough;
 	case ICE_SW_LKUP_ETHERTYPE:
 		off = (__force __be16 *)(eth_hdr + ICE_ETH_ETHTYPE_OFFSET);
 		*off = cpu_to_be16(f_info->l_data.ethertype_mac.ethertype);
@@ -771,7 +771,7 @@ ice_fill_sw_rule(struct ice_hw *hw, struct ice_fltr_info *f_info,
 		break;
 	case ICE_SW_LKUP_PROMISC_VLAN:
 		vlan_id = f_info->l_data.mac_vlan.vlan_id;
-		/* fall-through */
+		fallthrough;
 	case ICE_SW_LKUP_PROMISC:
 		daddr = f_info->l_data.mac_vlan.mac_addr;
 		break;

drivers/net/ethernet/intel/ice/ice_txrx.c

@@ -453,10 +453,10 @@ ice_run_xdp(struct ice_ring *rx_ring, struct xdp_buff *xdp,
 		break;
 	default:
 		bpf_warn_invalid_xdp_action(act);
-		/* fallthrough -- not supported action */
+		fallthrough;
 	case XDP_ABORTED:
 		trace_xdp_exception(rx_ring->netdev, xdp_prog, act);
-		/* fallthrough -- handle aborts by dropping frame */
+		fallthrough;
 	case XDP_DROP:
 		result = ICE_XDP_CONSUMED;
 		break;

drivers/net/ethernet/intel/ice/ice_xsk.c

@@ -816,10 +816,10 @@ ice_run_xdp_zc(struct ice_ring *rx_ring, struct xdp_buff *xdp)
 		break;
 	default:
 		bpf_warn_invalid_xdp_action(act);
-		/* fallthrough -- not supported action */
+		fallthrough;
 	case XDP_ABORTED:
 		trace_xdp_exception(rx_ring->netdev, xdp_prog, act);
-		/* fallthrough -- handle aborts by dropping frame */
+		fallthrough;
 	case XDP_DROP:
 		result = ICE_XDP_CONSUMED;
 		break;