ARM: 5637/1: [KS8695] Don't reference CLOCK_TICK_RATE in drivers

Stop referencing CLOCK_TICK_RATE in the KS8695 drivers, rather refer
to a KS8695_CLOCK_RATE.
Issue pointed out by Russell King on arm-linux-kernel mailing list.

Signed-off-by: Andrew Victor <linux@maxim.org.za>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>