abi-versions is not generated with --disable-versioning

[Roland McGrath]

> Trying to build glibc with --disable-versioning, I got a failure
> because abi-versions.h didn't exist.  We should either create a dummy
> file in this case or protect the inclusion in shlib-compat.h by an
> #ifdef DO_VERSIONING.

Oops.  That's from a change I just checked in last night.

> Roland, which way do you prefer?
> 
> For now I just changed the include in shlib-compat.h to:
> #ifdef DO_VERSIONING
> #include <abi-versions.h>	/* header generated by abi-versions.awk */
> #endif

I've just now checked in a change like this.


Roland