ARM: socfpga: Convert Arria10 to timer framework

ARM: socfpga: Convert Arria10 to timer framework

Switch the Arria10 from ad-hoc hardcoded timer to timer framework
and the DW APB timer driver. This allows the A10 to extract timer
information, like timer rate, from clock framework and thus DT
instead of having it hardcoded in U-Boot configuration files.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Chin Liang See <chin.liang.see@intel.com>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>