Always install locally built linux-headers and linux-image

These debs are special snowflakes in that they're not built with
the normal packaging rules. It's expected that locally built kernel
is always installed even with FETCH_PACKAGES=true .

Change-Id: I6d51479874c5d8ac2cfa76e40aba2a55539329f5
diff --git a/rootfs.mk b/rootfs.mk
index 1e29127..8f44087 100644
--- a/rootfs.mk
+++ b/rootfs.mk
@@ -58,8 +58,6 @@
 	libgstreamer1.0-0 \
 	libgstreamer-plugins-bad1.0-0 \
 	libgstreamer-plugins-base1.0-0 \
-	linux-headers-4.9.51-aiy \
-	linux-image-4.9.51-aiy \
 	mesa-common-dev \
 	uboot-imx \
 	wayland-protocols-imx \
@@ -143,6 +141,12 @@
 	sudo tar -xvf $(ROOTDIR)/cache/packages.tgz -C $(ROOTFS_DIR)/opt/aiy/
 	sudo chroot $(ROOTFS_DIR) bash -c 'apt-get update && apt-get install --allow-downgrades --no-install-recommends -y $(PRE_INSTALL_PACKAGES)'
 
+	sudo mount -t tmpfs none $(ROOTFS_DIR)/tmp
+	sudo cp $(PRODUCT_OUT)/packages/linux-headers-*-aiy_*_arm64.deb \
+		$(PRODUCT_OUT)/packages/linux-image-*-aiy_*_arm64.deb $(ROOTFS_DIR)/tmp
+	sudo chroot $(ROOTFS_DIR) bash -c 'apt-get install --allow-downgrades --no-install-recommends -y /tmp/*.deb'
+	sudo umount $(ROOTFS_DIR)/tmp
+
 	+make -f $(ROOTDIR)/build/rootfs.mk firmware
 	+make -f $(ROOTDIR)/build/rootfs.mk adjustments