spi: spi-sn-f-ospi: Use min_t instead of opencoding it

Use `min_t` instead of `min` with casting the individual arguments.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Link: https://lore.kernel.org/r/20230528195830.164669-2-lars@metafoo.de


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