rsa_sign now returns error if the underlying sign fails
rsa_sign now returns error if the underlying sign fails

svn path=/trunk/kdesupport/qca/; revision=662451

oktavarium/qca,sladage/qca,sladage/qca,JoshuaKolden/qca,KDE/qca,JoshuaKolden/qca,KDE/qca,JoshuaKolden/qca,JoshuaKolden/qca,Bjoe/qca,karolherbst/qca,Bjoe/qca,Esf-Software/qca,sladage/qca,Bjoe/qca,highfidelity/qca,Esf-Software/qca,oktavarium/qca,highfidelity/qca,highfidelity/qca,karolherbst/qca,highfidelity/qca,KDE/qca,KDE/qca,Bjoe/qca,sladage/qca,karolherbst/qca,Esf-Software/qca,oktavarium/qca,Esf-Software/qca,karolherbst/qca,oktavarium/qca