Boxlib: the tree_list can use large fonts, fix line number error

programs/develop/libraries/box_lib/trunk/tree_list.asm

@@ -2290,6 +2290,6 @@ align 4
 	jge @f
 		or al,0x30  ;<3B><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>塞 ᨬ<><E1A8AC><EFBFBD> '0'
 		stosb       ;<3B><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> al <20> <20>祪<EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> [edi]
-		mov byte[edi],0
+		mov word[edi],' ' ;add space symbol and 0
 	@@:
 	ret