All reports of multiarch-foreign-pkgconfig for the archive. The extended description of this tag is:
The package is architecture-dependent, ships a pkg-config file in a public, architecture-dependent pkg-config search path and is marked Multi-Arch: foreign. pkg-config will be unable to find this file, unless it is installed for a matching architecture, but the foreign marking says that the architecture should not matter.
Please remove the Multi-Arch: foreign stanza.
This tag has not been emitted in any package tested by Lintian.