buildinfo: only set ro.build.product on non-unified devices

Change-Id: I5dccba2172dade3dacc55d832a2042fce306b5f5
diff --git a/tools/buildinfo.sh b/tools/buildinfo.sh
index a5d0e21..559cd88 100755
--- a/tools/buildinfo.sh
+++ b/tools/buildinfo.sh
@@ -43,10 +43,9 @@
 echo "ro.wifi.channels=$PRODUCT_DEFAULT_WIFI_CHANNELS"
 echo "ro.board.platform=$TARGET_BOARD_PLATFORM"
 
-echo "# ro.build.product is obsolete; use ro.product.device"
-echo "ro.build.product=$TARGET_DEVICE"
-
 if [ "$TARGET_UNIFIED_DEVICE" == "" ] ; then
+  echo "# ro.build.product is obsolete; use ro.product.device"
+  echo "ro.build.product=$TARGET_DEVICE"
   echo "ro.product.model=$PRODUCT_MODEL"
   echo "ro.product.device=$TARGET_DEVICE"
   echo "# Do not try to parse description, fingerprint, or thumbprint"