eighthave authored Oct 29, 2019 and teor committed Nov 05, 2019

The current pkg-config setup has no sense of whether it is cross-compiling,
so it will detect things on the build system that are not present or are
wrong for the host system.  This forces the cross-compiling build to only
look for pkg-config .pc files in --prefix.

A version of this has been the setup for many years with the Android builds.

Fixes #32191

Signed-off-by: Hans-Christoph Steiner <hans@eds.org>