[WATCHDOG] i8xx_tco.c - remove support for ICH6 + ICH7

Temporary remove support for ICH6 + ICH7. In these newer TCO's
the watchdog timer has changed: the TCO_TMR register is not at
the TCOBASE+0x1 offset, but changed it's place to TCOBASE+0x12
and became 10 bit long [0:9]. (Kernel BUG 6031).

ICH6 + ICH7 support will be added in a new driver. Code is
under test.

Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Signed-off-by: Andrew Morton <akpm@osdl.org>