armv8: fix typo in LINUX_KERNEL_IMAGE_HEADER check

Fixes: 8163faf952 ARMv8: add optional Linux kernel image header

Signed-off-by: Mian Yousaf Kaukab <ykaukab@suse.de>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Tested-by: Andreas Färber <afaerber@suse.de>
1 file changed