MIPS: Netlogic: Platform NAND/NOR flash support

Changes to add support for the boot NOR flash on XLR boards and the
boot NAND/NOR flash drivers on the XLS boards.

Signed-off-by: Ganesan Ramalingam <ganesanr@netlogicmicro.com>
Signed-off-by: Jayachandran C <jayachandranc@netlogicmicro.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/3758/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>