drm/privacy_screen_x86: Add entry for ChromeOS privacy-screen

Add a static entry in the x86 table, to detect and wait for
privacy-screen on some ChromeOS platforms.

Please note that this means that if CONFIG_CHROMEOS_PRIVACY_SCREEN is
enabled, and if "GOOG0010" device is found in ACPI, then the i915 probe
shall return EPROBE_DEFER until a platform driver actually registers the
privacy-screen: https://hansdegoede.livejournal.com/25948.html

Signed-off-by: Rajat Jain <rajatja@google.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Benson Leung <bleung@chromium.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220107190208.95479-3-rajatja@google.com

drm/privacy-screen: honor acpi=off in detect_thinkpad_privacy_screen

when acpi=off is provided in bootarg, kernel crash with

[ 1.252739] BUG: kernel NULL pointer dereference, address: 0000000000000018
[ 1.258308] Call Trace:
[ 1.258490] ? acpi_walk_namespace+0x147/0x147
[ 1.258770] acpi_get_devices+0xe4/0x137
[ 1.258921] ? drm_core_init+0xc0/0xc0 [drm]
[ 1.259108] detect_thinkpad_privacy_screen+0x5e/0xa8 [drm]
[ 1.259337] drm_privacy_screen_lookup_init+0xe/0xe85 [drm]

The reason is that acpi_walk_namespace expects acpi related stuff
initialized but in fact it wouldn't when acpi is set to off. In this case
we should honor acpi=off in detect_thinkpad_privacy_screen().

Signed-off-by: Tong Zhang <ztong0001@gmail.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220123091004.763775-1-ztong0001@gmail.com

drm/privacy-screen: Add X86 specific arch init code

Add X86 specific arch init code, which fills the privacy-screen lookup
table by checking for various vendor specific ACPI interfaces for
controlling the privacy-screen.

This initial version only checks for the Lenovo Thinkpad specific ACPI
methods for privacy-screen control.

Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211005202322.700909-4-hdegoede@redhat.com