spi: stm32: introduction of stm32h7 SPI device mode support

Add support for stm32h7 to use SPI controller in device role.
In such case, the spi instance should have the spi-slave property
defined.

Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Link: https://lore.kernel.org/r/20230615075815.310261-5-valentin.caron@foss.st.com


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