mac-syphon: Remove obsolete translations

A commit f9cf458c1 removed syphon-inject but translations were left.

plugins/mac-syphon/data/locale/en-US.ini

@@ -1,8 +1,5 @@
 Syphon="Syphon Client"
 Source="Source"
-LaunchSyphonInject="Launch SyphonInject"
-Inject="Inject"
-Application="Application"
 SyphonLicense="Syphon License"
 Crop="Crop"
 Crop.origin.x="Crop left"