Nextgen release: Don't build super_empty.img

Bug: 183068624
Test: "m dist" on GSI and check the build artifacts under OUT and DIST
      directories, and check the contents of *-img-*.zip
Change-Id: I2474e5fd69534a5890eecd0c81e10a583e4423be
diff --git a/target/product/gsi_release.mk b/target/product/gsi_release.mk
index 539dbfa..e8f1c2e 100644
--- a/target/product/gsi_release.mk
+++ b/target/product/gsi_release.mk
@@ -65,3 +65,4 @@
 PRODUCT_BUILD_USERDATA_IMAGE := false
 PRODUCT_BUILD_VENDOR_IMAGE := false
 PRODUCT_BUILD_SUPER_PARTITION := false
+PRODUCT_BUILD_SUPER_EMPTY_IMAGE := false