remove documentation of obsolete switches

dcompiler.dd

@@ -704,9 +704,6 @@ dmd -cov -unittest myprog.d
 		)
 	  )
 
-	  $(SWITCH $(SWNAME -quiet),
-		suppress non-essential compiler messages
-	  )
 	  $(SWITCH $(SWNAME -release),
 
 		compile release version, which means not emitting run-time
@@ -720,12 +717,7 @@ dmd -cov -unittest myprog.d
 		command line, $(I args...), as the arguments to the program.
 		No .$(OBJEXT) or executable file is left behind.
 	  )
-$(COMMENT
-	  $(SWITCH $(SWNAME -safe),
-		Statically checks the modules being compiled to ensure they
-		conform to the $(LINK2 safed.html, safe memory model).
-	  )
-)
+
     $(UNIX
           $(SWITCH $(SWNAME -shared),
 		generate shared library