Skip the DCD loading if its length is 0
Skip the DCD loading if its length is 0

Some bootloaders are located in OCRAM and therefore don't
necessarily need a DCD table (QNX IPL on Nitrogen7).

Signed-off-by: Gary Bisson <ae64e258619d468ff9f32932b15678c58aa013b9@boundarydevices.com>

bwalle/imx_usb_loader,boundarydevices/imx_usb_loader