parser2 command-table helper hub failure ignored leaves bp->cmd_helper NULL inside a 'successfully' constructed firmware BIOS parser — latent whole-vtable NULL function-pointer call (v2 twin of DF-5075)

Summary

The hub correctly returns false for unmapped versions but bios_parser2.c:1987 ignores it and construct returns true - a live dc_bios with a NULL cmd_helper whose ~17 member calls in command_table2.c are all unguarded. On this build both DCN macros are force-defined so the only failing input (DCE_VERSION_UNKNOWN) triple-fails-closed at i2caux/gpio/res_pool before any BIOS command - strictly more locked than DF-5075, hence Info. Propagate-the-failure fix.