spi: stm32: fix missing device mode capability in stm32mp25

The STM32MP25 SOC has capability to behave in device mode however
missing .has_device_mode within its stm32mp25_spi_cfg structure leads
to not being able to enable the device mode.

Fixes: f6cd6623 ("spi: stm32: add st,stm32mp25-spi compatible supporting STM32MP25 soc")
Cc: stable@vger.kernel.org
Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Link: https://patch.msgid.link/20241010-spi-mp25-device-fix-v2-1-d13920de473d@foss.st.com


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