ntlm: Added support for SSPI package info query

Just as with the SSPI implementations of Digest and Negotiate added a
package info query so that libcurl can a) return a more appropriate
error code when the NTLM package is not supported and b) it can be of
use later to allocate a dynamic buffer for the Type-1 and Type-3
output tokens rather than use a fixed buffer of 1024 bytes.