arm: socfpga: pl310: Map SDRAM to 0x0

arm: socfpga: pl310: Map SDRAM to 0x0

Configure the PL310 address filter to make sure DRAM is mapped to 0x0.
This code also configures the "remap" register of NIC-301 and sets the
required 'mpuzero' bit.

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: Pavel Machek <pavel@denx.de>