[Fedora-packaging] Make empty debuginfo packages a build error?

[Ville Skyttä]

Hi,

How about making empty debuginfo packages a build error?  I can't think of a 
reason why an empty one would be a desired result, but empty ones do almost 
always indicate problems with the build.  Arch specific packages that 
expectedly don't have anything to place into the debuginfo package should 
explicitly disable it eg. with "%define debug_package %{nil}".

Also submitted as https://bugzilla.redhat.com/249956