Makefile: Fix UEFI devkey discovery

Include UEFI key directories (db/, kek/, pk/) in devkeys_install
target. Without this change, scripts/image_signing/sign_uefi.sh
aborted, complaining about missing UEFI keys.

BUG=b/465211305
TEST=presubmit
RELEASE_NOTE=None

cos-patch: bug
Change-Id: I4b6d1473eae831a7ba697fb69b4c0cffffdb971b
Reviewed-on: https://cos-review.googlesource.com/c/third_party/platform/vboot_reference/+/152103
Reviewed-by: Robert Kolchmeyer <rkolchmeyer@google.com>
Tested-by: Cusky Presubmit Bot <presubmit@cos-infra-prod.iam.gserviceaccount.com>
Reviewed-on: https://cos-review.googlesource.com/c/third_party/platform/vboot_reference/+/154334
1 file changed