GSS IOV flags

[Tom Yu]

Love expressed a desire to combine the flag and type fields of
gss_iov_buffer_desc_struct, but said he was willing to live without
it.  Looking at SSPI, the flag and type fields are combined.  Does
this change anybody's mind in favor of Love's proposed change?

If there is an existing API out there (SSPI), and we can make our
implementation look more like SSPI without causing problems for us, I
think we should.  Does anyone believe that making this change to align
more closely with SSPI will cause problems?