fix bugs in calculation of memory range to copy down.

c64/basic/basic_delete_line.s

@@ -26,6 +26,16 @@ basic_delete_line:
 	sec
 	sbc basic_current_line_ptr+0
 	sta tokenise_work3
+	lda tokenise_work4
+	sbc basic_current_line_ptr+1
+	sta tokenise_work4
+
+	jsr printf
+	.byte "LINE LENGTH IS $"
+	.byte $f0,<tokenise_work4,>tokenise_work4
+	.byte $f0,<tokenise_work3,>tokenise_work3
+	.byte $0d,0
+	
 	lda tokenise_work4
 	sbc #0
 	cmp #$00