arm: socfpga: timer: Pull the timer reload value from config file

arm: socfpga: timer: Pull the timer reload value from config file

The timer reload value is a property of the timer hardware and there
is no reason for this to be configurable. Place this into the timer
driver just like on the other hardware.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Chin Liang See <clsee@altera.com>
Cc: Dinh Nguyen <dinguyen@altera.com>
Cc: Albert Aribaud <albert.u.boot@aribaud.net>
Cc: Tom Rini <trini@ti.com>
Cc: Wolfgang Denk <wd@denx.de>
Cc: Pavel Machek <pavel@denx.de>
Acked-by: Dinh Nguyen <dinguyen@opensource.altera.com>
Acked-by: Pavel Machek <pavel@denx.de>