clk: st: STiH407: Support for clockgenC0

The patch added support for DT registration of ClockGenC0
It includes 2 c32 type PLL and a 660 Quadfs.

Signed-off-by: Gabriel Fernandez <gabriel.fernandez@linaro.org>
Signed-off-by: Olivier Bideau <olivier.bideau@st.com>
Acked-by: Peter Griffin <peter.griffin@linaro.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>