Hotfix: Reinstate the KC_DELT alias

quantum/quantum_keycodes.h

@@ -600,6 +600,8 @@ enum quantum_keycodes {
 #define KC_DOUBLE_QUOTE KC_DQT
 #define KC_DQUO KC_DQT
 
+#define KC_DELT KC_DELETE       // Del key (four letter code)
+
 // Alias for function layers than expand past FN31
 #define FUNC(kc) (QK_FUNCTION | (kc))