Remove obsolete .protocol file

Task: https://phabricator.kde.org/T14518

CMakeLists.txt

@@ -124,8 +124,6 @@ target_link_libraries(kio_audiocd
 
 install(TARGETS kio_audiocd  DESTINATION ${KDE_INSTALL_PLUGINDIR}/kf5/kio)
 
-install(FILES audiocd.protocol  DESTINATION  ${KDE_INSTALL_KSERVICES5DIR})
-
 ecm_qt_install_logging_categories(
     EXPORT AUDIOCD
     FILE kio_audiocd.categories

audiocd.protocol

-[Protocol]
-exec=kf5/kio/audiocd
-protocol=audiocd
-input=none
-output=filesystem
-listing=Name,Type,Size,Access
-reading=true
-writing=false
-makedir=false
-deleting=false
-linking=false
-moving=false
-Icon=media-optical-audio
-X-DocPath=kioslave5/audiocd/index.html
-Class=:local
-ShowPreviews=false