This patch is fixing missing fclose() calls
in error patch introduced by:
"tools: mkimage: Use fstat instead of stat to avoid malicious hacks"
(sha1: ebe0f53f)

Reported-by: Coverity (CID: 155064, 155065)
Signed-off-by: NMichal Simek <michal.simek@xilinx.com>
Reviewed-by: NSimon Glass <sjg@chromium.org>