ARM: socfpga: stratix10: Disable FPGA2SOC reset

Software must never reset FPGA2SOC bridge. This bridge must only be
reset by POR/COLD/WARM reset. Asserting the FPGA2SOC reset by software
can cause the SoC to lock-up if there are traffics being drived into
FPGA2SOC bridge.

Signed-off-by: Ang, Chee Hong <chee.hong.ang@intel.com>