build: add DTB to build artifacts

Instead of looking at a specific target type, examine the DTB build
variables to see if we have an unappended DTB file and include it
in this case, which will catch any build of that kind.

Bug: 28741987

Change-Id: Ibde2328c9c5d271ffffd32ba19f090a2ebb90270
diff --git a/build/tasks/dtb.mk b/build/tasks/dtb.mk
index 5a8d151..54206df 100644
--- a/build/tasks/dtb.mk
+++ b/build/tasks/dtb.mk
@@ -13,9 +13,11 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-# Make a zipfile containing the arm emulator's kernel.dtb
+# Make a zipfile containing the DTB if it has been built but not appended
+# to the kernel image already.
 
-ifeq ($(TARGET_DEVICE), brilloemulator_arm)
+ifdef TARGET_KERNEL_DTB
+ifndef TARGET_KERNEL_DTB_APPEND
 
 emul_name := $(TARGET_PRODUCT)
 ifeq ($(TARGET_BUILD_TYPE), debug)
@@ -36,3 +38,4 @@
 $(call dist-for-goals, dist_files, $(EMUL_ZIP))
 
 endif
+endif