Don't blindly assume the target agreed to transition to Full Feature Phase;
if we got a Login Response PDU without the "T" bit set, try again with
an empty request.  This fixes interoperability with COMSTAR.

Reviewed by:	mav@
Tested by:	mav@
MFC after:	1 week


git-svn-id: svn+ssh://svn.freebsd.org/base/head@271437 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f