i2c: i801: Hide Intel Birch Stream SoC TCO WDT

Hide the Intel Birch Stream SoC TCO WDT feature since it was removed.

On platforms with PCH TCO WDT, this redundant device might be rendering
errors like this:

[   28.144542] sysfs: cannot create duplicate filename '/bus/platform/devices/iTCO_wdt'

Fixes: 8c56f9ef ("i2c: i801: Add support for Intel Birch Stream SoC")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=220320


Signed-off-by: Chiasheng Lee <chiasheng.lee@linux.intel.com>
Cc: <stable@vger.kernel.org> # v6.7+
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://lore.kernel.org/r/20250901125943.916522-1-chiasheng.lee@linux.intel.com