Mark package as Multi-Arch: foreign

The requirement of this package is for cross compilation. The package is arch:all but does not define a Multi-Arch policy. As such, for cross-compilations, this package is unavailable.

As per https://wiki.debian.org/CrossBuildPackagingGuidelines the preferred option is to declare the package as Multi-Arch: foreign, for packages that are arch:all

Signed-off-by: Ritesh Raj Sarraf ritesh.sarraf@collabora.com