xi: More warning cleanup for input

Lots more const char stuff.

Remove duplicate defs of CoreKeyboardProc and CorePointerProc from
test/xi2/protocol-common.c

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

Xi/listdev.c

@@ -119,7 +119,7 @@ SizeDeviceInfo(DeviceIntPtr d, int *namesize, int *size)
  */
 
 static void
-CopyDeviceName(char **namebuf, char *name)
+CopyDeviceName(char **namebuf, const char *name)
 {
     char *nameptr = (char *) *namebuf;