sdm: Update vendor.display.config version in product package

Add vendor.display.config version 1.6, 1.7 and 1.8 in product package

Change-Id: I12d1d109c8819e30417ccdb0ee771db55858dc18
diff --git a/config/display-product.mk b/config/display-product.mk
index 5553d42..52f34da 100644
--- a/config/display-product.mk
+++ b/config/display-product.mk
@@ -19,6 +19,9 @@
     vendor.display.config@1.3.vendor \
     vendor.display.config@1.4.vendor \
     vendor.display.config@1.5.vendor \
+    vendor.display.config@1.6.vendor \
+    vendor.display.config@1.7.vendor \
+    vendor.display.config@1.8.vendor \
     modetest
 
 #QDCM calibration xml file for 2k panel