spi: spi-fsl-dspi: constify devtype_data

of_id->data is const, so instead of casting the pointer to drop its
const status, this patch constify the devtype_data pointer.

Signed-off-by: LABBE Corentin <clabbe.montjoie@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
1 file changed