Fix a printf format mismatch warning seen on 64-bit builds. Cc: Łukasz Majewski <l.majewski@samsung.com> Cc: Marek Vasut <marex@denx.de> Signed-off-by: Thierry Reding <treding@nvidia.com> Acked-by: Lukasz Majewski <l.majewski@samsung.com> Tested-by: Lukasz Majewski <l.majewski@samsung.com> Reviewed-by: Lukasz Majewski <l.majewski@samsung.com>