ARM: dts: stm32: Update sdmmc binding for stm32mp157c-ed1
Update some sdmmc properties which have been updated with
v4.19 DT bindings:
- st,dirpol becomes st,sig-dir
- st,negedge becomes st,neg-edge
- st,pin-ckin becomes st,use-ckin
Signed-off-by: Patrice Chotard <patrice.chotard@st.com>