Also disable dexpreopt for boot images for unbundled builds.

This fixes the tradefed build error caused by aosp/2582191.

Bug: 280440941
Test: `BUILD_BROKEN_DISABLE_BAZEL=true m dist` on tradefed branch.
Change-Id: I34c9fea0a5f7110c9b2bda1986df82afa3eafc79
diff --git a/core/config.mk b/core/config.mk
index 4300800..396aad0 100644
--- a/core/config.mk
+++ b/core/config.mk
@@ -546,8 +546,10 @@
 
 TARGET_BUILD_USE_PREBUILT_SDKS :=
 DISABLE_PREOPT :=
+DISABLE_PREOPT_BOOT_IMAGES :=
 ifneq (,$(TARGET_BUILD_APPS)$(TARGET_BUILD_UNBUNDLED_IMAGE))
   DISABLE_PREOPT := true
+  DISABLE_PREOPT_BOOT_IMAGES := true
 endif
 ifeq (true,$(TARGET_BUILD_UNBUNDLED))
   ifneq (true,$(UNBUNDLED_BUILD_SDKS_FROM_SOURCE))
@@ -558,6 +560,7 @@
 .KATI_READONLY := \
   TARGET_BUILD_USE_PREBUILT_SDKS \
   DISABLE_PREOPT \
+  DISABLE_PREOPT_BOOT_IMAGES \
 
 prebuilt_sdk_tools := prebuilts/sdk/tools
 prebuilt_sdk_tools_bin := $(prebuilt_sdk_tools)/$(HOST_OS)/bin
diff --git a/core/dex_preopt_config.mk b/core/dex_preopt_config.mk
index e36e2eb..7b9c4db 100644
--- a/core/dex_preopt_config.mk
+++ b/core/dex_preopt_config.mk
@@ -12,9 +12,15 @@
   # would result in passing bad arguments to dex2oat and failing the build.
   ENABLE_PREOPT :=
   ENABLE_PREOPT_BOOT_IMAGES :=
-else ifeq (true,$(DISABLE_PREOPT))
-  # Disable dexpreopt for libraries/apps, but do compile boot images.
-  ENABLE_PREOPT :=
+else
+  ifeq (true,$(DISABLE_PREOPT))
+    # Disable dexpreopt for libraries/apps, but may compile boot images.
+    ENABLE_PREOPT :=
+  endif
+  ifeq (true,$(DISABLE_PREOPT_BOOT_IMAGES))
+    # Disable dexpreopt for boot images, but may compile libraries/apps.
+    ENABLE_PREOPT_BOOT_IMAGES :=
+  endif
 endif
 
 # The default value for LOCAL_DEX_PREOPT