[recipes-kernel] modify the recipe to create kernel.tar.bz2

compress zImage and dtb files to a single kernel.tar.bz2 file.

recipes-kernel/linux/linux-fslc-imx_4.1-2.0.x.bbappend

@@ -4,4 +4,12 @@ FILESEXTRAPATHS_prepend := "${THISDIR}/${PN}:"
 
 SRCREV = "1c7f6c63f9d0f4c3b8ba69236beea46345af821f"
 
-COMPATIBLE_MACHINE = "(mx6|mx7|vesta)"
\ No newline at end of file
+COMPATIBLE_MACHINE = "(mx6|mx7|vesta)"
+
+do_compress () {
+	cd ${DEPLOY_DIR_IMAGE}
+	tar -hczvf kernel.tar.bz2 zImage zImage-310-00110-0003.dtb zImage-vesta-*.dtb
+}
+
+addtask compress after do_deploy before do_build
+