ARM: STi: DT: STih407: STih410: Add clk_ignore_unused to kernel bootargs

At the moment we don't take a reference on some core interconnect
clocks which means when CCF turns off unused clocks the SoC will
hang. As a temp soltuion we will boot with clk_ignore_unused
parameter for all b2120 boards.
Signed-off-by: NPeter Griffin <peter.griffin@linaro.org>
Acked-by: NLee Jones <lee.jones@linaro.org>
Signed-off-by: NMaxime Coquelin <maxime.coquelin@st.com>

arch/arm/boot/dts/stih407-b2120.dts

@@ -15,7 +15,7 @@
 	compatible = "st,stih407-b2120", "st,stih407";
 
 	chosen {
-		bootargs = "console=ttyAS0,115200";
+		bootargs = "console=ttyAS0,115200 clk_ignore_unused";
 		linux,stdout-path = &sbc_serial0;
 	};
 

arch/arm/boot/dts/stih410-b2120.dts

@@ -14,7 +14,7 @@
 	compatible = "st,stih410-b2120", "st,stih410";
 
 	chosen {
-		bootargs = "console=ttyAS0,115200";
+		bootargs = "console=ttyAS0,115200 clk_ignore_unused";
 		linux,stdout-path = &sbc_serial0;
 	};