spi: stm32: always perform registers configuration prior to transfer

SPI registers content may have been lost upon suspend/resume sequence.
So, always compute and apply the necessary configuration in
stm32_spi_transfer_one_setup routine.

Signed-off-by: Alain Volmat <alain.volmat@st.com>
Link: https://lore.kernel.org/r/1597043558-29668-6-git-send-email-alain.volmat@st.com
Signed-off-by: Mark Brown <broonie@kernel.org>