When X509_KEY_USAGE or szOID_KEY_USAGE are used for the lpszStructType with CryptEncodeObject, CryptEncodeObjectEx, CryptDecodeObject, or CryptDecodeObjectEx the following details apply.
"2.5.29.15"
pvStructInfo points to a CRYPT_BIT_BLOB.
It has the same bit definitions as CERT_KEY_ATTRIBUTES_INFO's IntendedKeyUsage member.