spi: spi-mtk-nor: support 36bit dma addressing

This patch enables 36bit dma address support to spi-mtk-nor.
Currently this is enabled only for mt8192-nor.

Signed-off-by: Ikjoon Jang <ikjn@chromium.org>
Link: https://lore.kernel.org/r/20201006155010.v5.3.Id1cb208392928afc7ceed4de06924243c7858cd0@changeid


Signed-off-by: Mark Brown <broonie@kernel.org>