CMake subproject support, part 3: export MAGNUMPLUGINS_* variables.

This way the FindMagnumPlugins.cmake module will have everything found
already and so it will do only some additional management on top.

src/MagnumPlugins/AnyAudioImporter/CMakeLists.txt

@@ -59,3 +59,6 @@ if(BUILD_TESTS)
     target_link_libraries(MagnumAnyAudioImporterTestLib ${MAGNUM_LIBRARIES} ${MAGNUM_AUDIO_LIBRARIES})
     add_subdirectory(Test)
 endif()
+
+# Magnum AnyAudioImporter library for superprojects
+set(MAGNUMPLUGINS_ANYAUDIOIMPORTER_LIBRARY AnyAudioImporter CACHE INTERNAL "")

src/MagnumPlugins/AnyImageConverter/CMakeLists.txt

@@ -55,3 +55,6 @@ if(BUILD_TESTS)
     target_link_libraries(MagnumAnyImageConverterTestLib ${MAGNUM_LIBRARIES})
     add_subdirectory(Test)
 endif()
+
+# Magnum AnyImageConverter library for superprojects
+set(MAGNUMPLUGINS_ANYIMAGECONVERTER_LIBRARY AnyImageConverter CACHE INTERNAL "")

src/MagnumPlugins/AnyImageImporter/CMakeLists.txt

@@ -64,3 +64,6 @@ if(BUILD_TESTS)
     target_link_libraries(MagnumAnyImageImporterTestLib ${MAGNUM_LIBRARIES})
     add_subdirectory(Test)
 endif()
+
+# Magnum AnyImageImporter library for superprojects
+set(MAGNUMPLUGINS_ANYIMAGEIMPORTER_LIBRARY AnyImageImporter CACHE INTERNAL "")

src/MagnumPlugins/AnySceneImporter/CMakeLists.txt

@@ -56,3 +56,6 @@ if(BUILD_TESTS)
     target_link_libraries(MagnumAnySceneImporterTestLib ${MAGNUM_LIBRARIES})
     add_subdirectory(Test)
 endif()
+
+# Magnum AnySceneImporter library for superprojects
+set(MAGNUMPLUGINS_ANYSCENEIMPORTER_LIBRARY AnySceneImporter CACHE INTERNAL "")