Coverity issues

[xhanulik]

Fix for recently found CID 424593, 424594.

Checklist

• Documentation is added or updated
• New files have a LGPL 2.1 license statement
• PKCS#11 module is tested

[Jakuje]

nit: In the ways out: the check for non-NULL ctx are not needed

And once we touch it, we should probably check the return value of EVP_CIPHER_CTX_set_padding too.

[xhanulik]

And once we touch it, we should probably check the return value of EVP_CIPHER_CTX_set_padding too.

From documentation, EVP_CIPHER_CTX_set_padding() always returns 1. But I will remove the unneeded ifs.

[Jakuje]

From documentation, EVP_CIPHER_CTX_set_padding() always returns 1. But I will remove the unneeded ifs.

Good point. But it might change so sanity-checking the return value should not hurt.

[xhanulik]

Thanks for review, merging.