soc/intel/common/block/acpi: Return existing Object for _DSM subfunction

Currently the LPIT Get Constraints _DSM subfunction returns a package
containing the path to a nonexistent device (\NULL). This is used to
work around an issue with Windows, where returning an empty package will
cause a BSOD.  However, using this non-existent device can also cause
confusion, as on Linux, it shows an error in dmesg, e.g.

    ACPI Error: AE_NOT_FOUND, While resolving a named reference package
    element - \NULL (20200925/dspkginit-438)

Therefore, this patch modifies this returned package slightly to include
the path to ACPI_CPU_STRING for CPU 0, which should always be emitted on
Intel platforms that use the PEP driver.

Tested on google/brya0 on ChromeOS 5.10 kernel
Tested with current Windows 11 ISO

Signed-off-by: Tim Wawrzynczak <twawrzynczak@chromium.org>
Change-Id: If74a1620ff0de33bcdba06e1225c5e28c64253e1
Reviewed-on: https://review.coreboot.org/c/coreboot/+/61868
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Matt DeVillier <matt.devillier@gmail.com>
Reviewed-by: Shobhit Srivastava <shobhit.srivastava@intel.corp-partner.google.com>

0 files changed, 0 insertions, 0 deletions