board: fsl_validate: Fix Double free Issue

Remove Double free issue from calc_img_key_hash() and
calc_esbchdr_esbc_hash() function.
Verified the secure boot changes using lx2162aqds board.

Signed-off-by: Kshitiz Varshney <kshitiz.varshney@nxp.com>
Reviewed-by: Priyanka Jain <priyanka.jain@nxp.com>
2 files changed