The LID state provided by ACPI on the Surface 3 is not accurate.
The ACPI node doesn't get notified on LID open, which means the
LID input switch stays close most of the time.

Fortunatelly, there is a WMI method which directly queries the
GPIO underneath the LID state, so it's far more reliable than ACPI.
To get the notifications that the LID was opened/closed, we can
rely on the ACPI notification of the touchscreen: the DSDT shows
that the touchscreen will get notified on close/open as it also
controls its _STA method.

Note that we need to set the tag "power-switch" to the LID
input node through a udev rule for logind to accept it:

SUBSYSTEM=="input", KERNEL=="event*", KERNELS=="surface3-wmi", \
	TAG+="power-switch"
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>