kdrive/ephyr: ddxUseMsg is supposed to return

I'm not sure why ephyr thinks that ddxUseMsg shouldn't return, but
it's not declared to exit.

Signed-off-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Adam Jackson <ajax@redhat.com>

hw/kdrive/ephyr/ephyrinit.c

@@ -149,8 +149,6 @@ ddxUseMsg(void)
     ErrorF
         ("-title [title]       set the window title in the WM_NAME property\n");
     ErrorF("\n");
-
-    exit(1);
 }
 
 void