ARM: drop <mach/timex.h> for !ARCH_MULTIPLATFORM, too

While <mach/timex.h> isn't used for multi-platform builds since long it
still is for "normal" builds. As the previous patches fix all sites to
not make use of this per-platform file, it can go now for good also for
platforms that are not (yet) converted to multi-platform.

While at it there are no users of CLOCK_TICK_RATE any more, so also drop
the dummy #define.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

arch/arm/mach-ebsa110/include/mach/timex.h

@@ -1,19 +0,0 @@
-/*
- *  arch/arm/mach-ebsa110/include/mach/timex.h
- *
- *  Copyright (C) 1997, 1998 Russell King
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- *  EBSA110 architecture timex specifications
- */
-
-/*
- * On the EBSA, the clock ticks at weird rates.
- * This is therefore not used to calculate the
- * divisor.
- */
-#define CLOCK_TICK_RATE		47894000
-