Fix various typos with codespell

Found via `codespell -q 3 -S ./thirdparty,*.po,./DONORS.md -L ackward,ang,ans,ba,beng,cas,childs,childrens,dof,doubleclick,fave,findn,hist,inout,leapyear,lod,nd,numer,ois,ony,paket,seeked,sinc,switchs,te,uint`

platform/linuxbsd/display_server_x11.cpp

@@ -2167,7 +2167,7 @@ void DisplayServerX11::_handle_key_event(WindowID p_window, XKeyEvent *p_event,
 	// still works in half the cases. (won't handle deadkeys)
 	// For more complex input methods (deadkeys and more advanced)
 	// you have to use XmbLookupString (??).
-	// So.. then you have to chosse which of both results
+	// So then you have to choose which of both results
 	// you want to keep.
 	// This is a real bizarreness and cpu waster.