To fit with latest rtc driver updates, rtc st,syscfg property must contain
the control register offset of pwrcfg and the mask corresponding to the
DBP (Disable Backup Protection) bit.
Signed-off-by: NAmelie Delaunay <amelie.delaunay@st.com>
Signed-off-by: NAlexandre Torgue <alexandre.torgue@st.com>