Fix error decrypt
Fix error decrypt

Fix error in decrypt, when using iv and key without password. No need
write and read salt without password, because salt uses only for
generated iv and key.

TrustedPlus/crypto,Digt/trusted-crypto,TrustedPlus/crypto,TrustedPlus/trusted-crypto,Digt/trusted-crypto,TrustedPlus/trusted-crypto,TrustedPlus/crypto,Digt/trusted-crypto,TrustedPlus/crypto,TrustedPlus/trusted-crypto,Digt/trusted-crypto,TrustedPlus/trusted-crypto,Digt/trusted-crypto,TrustedPlus/crypto,TrustedPlus/trusted-crypto