Support to build vendor.img

Bug: 8341435
Change-Id: I2db7970936984d38aed35054e3f695d298f4e512
diff --git a/core/main.mk b/core/main.mk
index e671722..49e0a9a 100644
--- a/core/main.mk
+++ b/core/main.mk
@@ -749,6 +749,9 @@
 .PHONY: cacheimage
 cacheimage: $(INSTALLED_CACHEIMAGE_TARGET)
 
+.PHONY: vendorimage
+vendorimage: $(INSTALLED_VENDORIMAGE_TARGET)
+
 .PHONY: bootimage
 bootimage: $(INSTALLED_BOOTIMAGE_TARGET)
 
@@ -774,6 +777,7 @@
 	$(INSTALLED_RECOVERYIMAGE_TARGET) \
 	$(INSTALLED_USERDATAIMAGE_TARGET) \
 	$(INSTALLED_CACHEIMAGE_TARGET) \
+	$(INSTALLED_VENDORIMAGE_TARGET) \
 	$(INSTALLED_FILES_FILE)
 
 # dist_files only for putting your library into the dist directory with a full build.