* @return 0 if ok, -1 on error
*/
static int fit_image_process_sig(const char *keydir, void *keydest,
void *fit, const char *image_name,
int noffset, const void *data, size_t size,
* @return 0 if ok, -1 on error
*/
static int fit_image_process_sig(const char *keydir, void *keydest,
void *fit, const char *image_name,
int noffset, const void *data, size_t size,