Pekka Paalanen authored Nov 11, 2019 and Daniel Stone committed Jan 30, 2020

The ivi-layout-test comprises of two halves: the client and the plugin. This
migrates the test to the new test harness.

In the old harness, the plugin was built as the test in meson.build and it fork
& exec'd the client part. In the new harness client tests start from the client
program which sets up the compositor in-process, so now the client is built as
the test in meson.build and the plugin is just an additional file.

Therefore there is not need for the plugin for fork & exec anything anymore, so
all that code is removed.

Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.com>