fix(stm32mp1_clk): correctly manage RTC clock source

The clksrc value contains the RCC register address and the clock
source number. When applying the clock source, we should filter out
the RCC register address from the given value.

Signed-off-by: Yann Gautier <yann.gautier@foss.st.com>
Change-Id: I4345b03de7b9afd1df78df4131431cf1eb43ec17
1 file changed