libtasn1 fail to process CHOICE inside CHOICE syntax

[d_bulavski]

Package: libtasn1
Version: 3.4

asn1_der_decoding() fails to process DER-encoded data for ASN.1 syntax
with CHOICE inside CHOICE.

Syntax example from RFC 5055.
PKCReference ::= CHOICE {
    cert        [0] Certificate,
    pkcRef      [1] SCVPCertID }

ACReference ::= CHOICE {
    attrCert    [2] AttributeCertificate,
    acRef       [3] SCVPCertID }

CertReference::= CHOICE {
    pkc         PKCReference,
    ac          ACReference }

asn1_der_decoding() returns ASN1_DER_ERROR for DER data encoded
with asn1_der_coding().