um: Fix xor.h include

Two independent changes here ended up going into the tree
one after another, without a necessary rename, fix that.
Reported-by: Thomas Meyer <thomas@m3y3r.de>
Fixes: f185063b ("um: Move timer-internal.h to non-shared")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

arch/um/include/asm/xor.h

 /* SPDX-License-Identifier: GPL-2.0 */
 #include <asm-generic/xor.h>
-#include <shared/timer-internal.h>
+#include <linux/time-internal.h>
 
 /* pick an arbitrary one - measuring isn't possible with inf-cpu */
 #define XOR_SELECT_TEMPLATE(x)	\