clk: stm32f4: Add RTC clock

This patch introduces the support of the RTC clock.
RTC clock can have 3 sources: lsi, lse and hse_rtc.

Signed-off-by: Gabriel Fernandez <gabriel.fernandez@st.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
This commit is contained in:
Gabriel Fernandez 2016-10-21 11:23:29 +02:00 • committed by Stephen Boyd
commit 4261a881cf