xilinx: dfu: Fill directly update_info.dfu_string

Directly fill update_info.dfu_string to prepare platforms to switch
from using dfu_alt_info variable to dfu_string which contains description
for capsule update when switch is done.

Signed-off-by: Michal Simek <michal.simek@amd.com>
Reviewed-by: Mattijs Korpershoek <mkorpershoek@baylibre.com>
Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
3 files changed