null pointer defer in HTMLlineproc0()

[kcwu]

input

00000000: 3c6d 6574 6120 6368 6172 7365 743d 6762  <meta charset=gb
00000010: 3138 3033 303e 0a3c 696e 7075 740b 7661  18030>.<input.va
00000020: 6c75 653d 803c 7461 626c 653e            lue=.<table>

gdb --args w3m -T text/html -dump file

Program received signal SIGSEGV, Segmentation fault.
0x000000000042b440 in HTMLlineproc0 (line=0x7beef5 "\n", h_env=0x7fffffffc3d0, internal=0) at file.c:6333
6333            int pre_mode = (obuf->table_level >= 0) ? tbl_mode->pre_mode :
(gdb) p obuf->table_level
$1 = 0
(gdb) p tbl_mode
$2 = (struct table_mode *) 0x0

This is found by afl-fuzz.

[tats]

Fixed, thank you.