gcc cvs (010922) build error on ia64

[David Edelsohn]

	GCC 3.0.2 and the trunk now define TARGET_VTABLE_USES_DESCRIPTORS
on IA-64.  Is that an incompatible change?

	On a related note, should all targets with function descriptors
(e.g., AIX and 64-bit PowerPC Linux) use that macro as well?

Thanks, David