tools/imagetool: Fix segfault when tparams->verify_header is NULL

On some image types like i.MX8 and i.MX8M, the verify_header function
is not implemented.

Before this commit, no check on tparams->verify_header was done causing
a segfault if NULL. Now, a proper error message is printed.

Signed-off-by: Nicolas Heemeryck <nicolas.heemeryck@gmail.com>
1 file changed