memory: tegra: Prepare for supporting multiple intmask registers

Add a new structure for the intmask register e.g. MC_INTMASK_0 and
it's mask value. Add an array of these new structures to prepare for
supporting multiple intmask registers. This is done in preparation for
adding support for Tegra264 which supports multiple intmask registers.

Signed-off-by: Ketan Patil <ketanp@nvidia.com>
Reviewed-by: Jon Hunter <jonathanh@nvidia.com>
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Link: https://patch.msgid.link/20260226163115.1152181-6-ketanp@nvidia.com
[krzk: Fix checkpatch warning]
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>