platform/x86: thinkpad_acpi: Simplify known_ev handling

Modify how known_ev event is handled in preparation for adding new hkey
event range.

Signed-off-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Link: https://lore.kernel.org/r/20240417173124.9953-1-mpearson-lenovo@squebb.ca
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Tested-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20240424122834.19801-22-hdegoede@redhat.com

drivers/platform/x86/thinkpad_acpi.c

@@ -3845,6 +3845,7 @@ static void hotkey_notify(struct ibm_struct *ibm, u32 event)
 		}
 
 		send_acpi_ev = true;
+		known_ev = false;
 
 		switch (hkey >> 12) {
 		case 1:
@@ -3868,8 +3869,6 @@ static void hotkey_notify(struct ibm_struct *ibm, u32 event)
 				/* FIXME: kick libata if SATA link offline */
 				known_ev = true;
 				break;
-			default:
-				known_ev = false;
 			}
 			break;
 		case 4:
@@ -3892,11 +3891,8 @@ static void hotkey_notify(struct ibm_struct *ibm, u32 event)
 				tpacpi_send_radiosw_update();
 				send_acpi_ev = 0;
 				known_ev = true;
-				break;
 			}
-			fallthrough;	/* to default */
-		default:
-			known_ev = false;
+			break;
 		}
 		if (!known_ev) {
 			pr_notice("unhandled HKEY event 0x%04x\n", hkey);