mmc: mmci: stm32: set feedback clock when using delay block

mmc: mmci: stm32: set feedback clock when using delay block

The feedback clock is used only for SDR104 & HS200 modes, and when
delay block is used (frequency is higher than 50 MHz). The tuning
procedure is then only required for those modes. Skip the procedure
for other modes.
The setting of this feedback clock is done just after enabling delay
block, and before configuring it.

Signed-off-by: Yann Gautier <yann.gautier@foss.st.com>
Signed-off-by: Christophe Kerello <christophe.kerello@foss.st.com>
Link: https://lore.kernel.org/r/20230613150148.429828-1-yann.gautier@foss.st.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>