5.1p build problem on SCO OSR6

[Roger Cornelius]

Build of 5.1p1 fails on SCO OSR6 with the error:

UX:acomp: ERROR: "addrmatch.c", line 100: undefined struct/union member: sin6_scope_id

configure checks for presence of struct sockaddr_in6 and uses the system
declaration if found (via #define HAVE_STRUCT_SOCKADDR_IN6 in config.h)
If not found, the struct is declared in openbsd-compat/fake-rfc2553.h.
OSR6 has struct sockaddr_in6 but it does not include the sin6_scope_id
member.  The declaration in fake-rfc2553.h does include this member,
which is referenced in addrmatch.c.

So the problem seems to be, openssh erroneously assumes the presence of
sin6_scope_id if struct sockaddr_in6 is present.  This isn't true on
OSR6 (and maybe others??).
-- 
Roger Cornelius        rac at tenzing.org