It's reported that some buggy BIOS tables can contain 2 DSDT ECs, one of
them is invalid but acpi_ec_dsdt_probe() fails to pick the valid one.
This patch simply enhances sanity checks in ec_parse_device() as a
workaround to skip probing wrong namespace ECs.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=195651Tested-by: NDaniel Drake <drake@endlessm.com>
Signed-off-by: NLv Zheng <lv.zheng@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>