[scripts] fix /lib/dts search path in mkloopcard.sh

scripts/mkloopcard.sh

@@ -251,7 +251,7 @@ fi
 for dtb in ${DTB_FILES}; do
 	echo "Requested to copy dtb: ${dtb}"
 	# expect to have just one kernel installed
-	dtb_files=$(find /lib/dts -name "${dtb}" -print)
+	dtb_files=$(find "${tmp_dir}/lib/dts" -name "${dtb}" -print)
 	for dtb_file in ${dtb_files}; do
 		echo "Copying dtb: ${dtb_file} to ${boot_tmp_dir}/"
 		cp "${dtb_file}" "${boot_tmp_dir}/" || exit 1