drivers: spi: spi_ll_stm32: Fix uncleared MODF flag
drivers: spi: spi_ll_stm32: Fix uncleared MODF flag

Clear raised MODF flag, if not done the flag stay set forever.

Fixes https://github.com/zephyrproject-rtos/zephyr/issues/17363

Signed-off-by: Yaël Boutreux <47135fe71614bab2c897b5d61521525494a92068@st.com>
Signed-off-by: Arnaud Pouliquen <b379f9d268ae6bc79bae62bbf7d1708239982b68@st.com>
Signed-off-by: Alexandre Torgue <2def9cba63f53479ee2284c78700c4765096eb7e@st.com>

finikorg/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,nashif/zephyr,Vudentz/zephyr,zephyrproject-rtos/zephyr,galak/zephyr,galak/zephyr,finikorg/zephyr,Vudentz/zephyr,finikorg/zephyr,nashif/zephyr,finikorg/zephyr,galak/zephyr,Vudentz/zephyr,nashif/zephyr,Vudentz/zephyr,Vudentz/zephyr,zephyrproject-rtos/zephyr,galak/zephyr,Vudentz/zephyr,finikorg/zephyr,zephyrproject-rtos/zephyr,nashif/zephyr,nashif/zephyr,galak/zephyr