ACPI: sbs: use EC rather than I2C

SBS is based on EC function(ec_read/ec_write).
Not needed using of I2C structures/functions ... is removed.
SBS does not depend on I2C now.
Signed-off-by: Vladimir Lebedev <vladimir.p.lebedev@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>