Add vendor_dlkm partition.

Test: define vendor_dlkm for CF.
Bug: 156020364

Change-Id: I459059e1c20df7a285a377b8b3bbc8decc60b124
diff --git a/tools/releasetools/merge_target_files.py b/tools/releasetools/merge_target_files.py
index ed42b20..ad991ca 100755
--- a/tools/releasetools/merge_target_files.py
+++ b/tools/releasetools/merge_target_files.py
@@ -197,6 +197,7 @@
     'PREBUILT_IMAGES/*',
     'RADIO/*',
     'VENDOR/*',
+    'VENDOR_DLKM/*',
 )
 
 # VENDOR_EXTRACT_SPECIAL_ITEM_LIST is a list of items to extract from the
@@ -223,6 +224,7 @@
     'SYSTEM/',
     'SYSTEM_OTHER/',
     'VENDOR/',
+    'VENDOR_DLKM/',
 )