ACPI: EC: If ECDT is not found, look up EC in DSDT.

Some ASUS laptops access EC space from device _INI methods, but do not
provide ECDT for early EC setup. In order to make them function properly,
there is a need to find EC is DSDT before any _INI is called.

Similar functionality was turned on by acpi_fake_ecdt=1 command line
before. Now it is on all the time.

http://bugzilla.kernel.org/show_bug.cgi?id=8598

Signed-off-by: Alexey Starikovskiy <astarikovskiy@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>