Mark 'test', 'test-report', 'perf-report' and 'full-report' as PHONY in
docs/Makefile.am to prevent recursion of gtester into the documentation
subdirectories. Stop including Makefile.decl from these directories
since it is no longer necessary.
This will clear up the warnings about EXTRA_DIST being defined once in
gtk-doc.make and again in Makefile.decl.
This avoids the generated types (e.g. ExampleAnimal, ExampleCat,
ExampleObject and ExampleObjectManagerClient) being referenced in the
core gio docs. This was requested by Matthias.
Signed-off-by: David Zeuthen <davidz@redhat.com>