Update vboot submodule to upstream main

Updating from commit id ccc56f4:
    vboot: add x86 SHA256 ext support

to commit id 4423276:
    crossystem: add a hwid override mechanism from chromeos-config

Signed-off-by: Thejaswani Putta <thejaswani.putta@intel.com>
Change-Id: I7bd73b9f6c0492f96c336b61e21ecae37b8f3606
Reviewed-on: https://review.coreboot.org/c/coreboot/+/57322
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Tim Wawrzynczak <twawrzynczak@chromium.org>
Reviewed-by: Thejaswani Putta <thejaswani.putta@intel.corp-partner.google.com>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>

3rdparty/vboot

@@ -1 +1 @@
-Subproject commit ccc56f46c51fa9d0c2b3c086ace97c14fe887c32
+Subproject commit 4423276b4607cf1b3975eaff57d17869c0620ecd