intel/i82801cx: Move HAVE_HARD_RESET to southbridge

intel/i82801cx: Move HAVE_HARD_RESET to southbridge

No in-tree board using that chipset has it not selected, so move
selection from boards to southbridge.

Change-Id: Ifba0b65d81af60774f368d151e935ae1cc768336
Signed-off-by: Patrick Georgi <patrick@georgi-clan.de>
Reviewed-on: http://review.coreboot.org/662
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Tested-by: build bot (Jenkins)