Align the implementation to rsa_add_verify_data() by writing the modulus
and r-squared properties with the same length as the key itself. This
fixes signature verification issues when one of the parameters has
leading zeros.
Reported-by: Hans Gfirtner (Nokia) <hans.gfirtner@nokia.com>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>