one more module grandfathered with a user tag

Change-Id: I22d60c33df06cfe0bfd2041a611c762e6e662c94
diff --git a/core/user_tags.mk b/core/user_tags.mk
index 1cefd78..787b20e 100644
--- a/core/user_tags.mk
+++ b/core/user_tags.mk
@@ -98,6 +98,7 @@
 	dexdump \
 	dexlist \
 	dexopt \
+	dexpreopt \
 	dex-tools \
 	dhcpcd \
 	dhcpcd.conf \