Really change the rootfs to 2G

Change-Id: I6c976199f6eb7d0969d3fdc40d15406e147649ac
diff --git a/rootfs.mk b/rootfs.mk
index f716af4..87aa383 100644
--- a/rootfs.mk
+++ b/rootfs.mk
@@ -52,7 +52,7 @@
 	+make -f $(ROOTDIR)/build/debootstrap.mk validate-bootstrap-tarball
 
 	mkdir -p $(ROOTFS_DIR)
-	fallocate -l 12834570240 $(ROOTFS_RAW_IMG)
+	fallocate -l 2G $(ROOTFS_RAW_IMG)
 	mkfs.ext4 -j $(ROOTFS_RAW_IMG)
 	tune2fs -o discard $(ROOTFS_RAW_IMG)
 	sudo mount -o loop $(ROOTFS_RAW_IMG) $(ROOTFS_DIR)