[Pkg-postgresql-public] disable sysctl stuff on non-linux

[Peter Eisentraut]

On Mon, 2013-04-08 at 11:09 +0200, Martin Pitt wrote:
> Christoph Berg [2013-04-08 10:07 +0200]:
> > Erm, postgresql-common is an arch: all package...
> 
> *blush*, sorry. I reverted this.

Oops, sorry.  I guess the proper way to do this might be via ucf, but
that doesn't seem worth it.  In the long term (PG 9.3), the need for
this file will go away anyway.