Free memory on an error path
Free memory on an error path

The function a2i_ASN1_STRING can encounter an error after already
allocating a buffer. It wasn't always freeing that buffer on error.

Reviewed-by: Richard Levitte <5fb523282dd7956571c80524edc2dccfa0bd8234@openssl.org>

openssl/openssl,openssl/openssl,openssl/openssl,openssl/openssl,openssl/openssl,openssl/openssl