pull up r22084 from trunk

acc_ctx_new() can return an error condition without establishing a
SPNEGO context structure.  This can cause a null pointer dereference
in cleanup code in spnego_gss_accept_sec_context().

https://github.com/krb5/krb5/commit/436064dc47dc336c44485068fb2f2fbc6cf840f4
Commit By: tlyu
Revision: 22104
Changed Files:
U   branches/krb5-1-6/src/lib/gssapi/spnego/spnego_mech.c