add new system file

hc

2024-02-20 102a0743326a03cd1a1202ceda21e175b7d3575c

 kernel/kernel/debug/kdb/kdb_keyboard.c
..
..
@@ -173,11 +173,11 @@
173
173
 	case KT_LATIN:
174
174
 		if (isprint(keychar))
175
175
 			break;		/* printable characters */
176
-		/* drop through */
176
+		fallthrough;
177
177
 	case KT_SPEC:
178
178
 		if (keychar == K_ENTER)
179
179
 			break;
180
-		/* drop through */
180
+		fallthrough;
181
181
 	default:
182
182
 		return -1;	/* ignore unprintables */
183
183
 	}