Remove unneccesary casts from WriteToClient calls

Casting return to (void) was used to tell lint that you intended
to ignore the return value, so it didn't warn you about it.

Casting the third argument to (char *) was used as the most generic
pointer type in the days before compilers supported C89 (void *)
(except for a couple places it's used for byte-sized pointer math).

Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Reviewed-by: Keith Packard <keithp@keithp.com>
Tested-by: Daniel Stone <daniel@fooishbar.org>

Xi/setmmap.c

@@ -140,5 +140,5 @@ SRepXSetDeviceModifierMapping(ClientPtr client, int size,
 {
     swaps(&rep->sequenceNumber);
     swapl(&rep->length);
-    WriteToClient(client, size, (char *) rep);
+    WriteToClient(client, size, rep);
 }