dts: stm32: fix GPU OPP description for STM32MP23x

Since commit e80e43f ("plat-stm32mp: introduce GPU OPP driver") the
GPU opp are described in device tree and are used for SCMI power domain.

But the OPP for STM32MP23 SoC is correctly defined as it is limited at
400MHz.

Fixes: 7f71868 ("dts: stm32: add GPU OPP description in stm32mp235.dtsi")
Signed-off-by: Patrick Delaunay <[email protected]>
Change-Id: Ibd65f24a874392fa25e44d9149356535dbd582ab
Reviewed-on: https://gerrit.st.com/c/mpu/oe/optee/optee_os/+/439608
ACI: CITOOLS <[email protected]>
Reviewed-by: Thomas BOURGOIN <[email protected]>

Author: patrickdelaunay

core/arch/arm/dts/stm32mp235.dtsi

@@ -10,19 +10,12 @@
 	gpu_opp_table: opp-table-gpu {
 		compatible = "operating-points-v2";
 
-		opp-800000000 {
-			opp-hz = /bits/ 64 <800000000>;
+		opp-400000000 {
+			opp-hz = /bits/ 64 <400000000>;
 			opp-microvolt = <800000>;
 			opp-supported-hw = <0x3>;
 			st,opp-default;
 		};
-
-		opp-900000000 {
-			opp-hz = /bits/ 64 <900000000>;
-			opp-microvolt = <900000>;
-			opp-supported-hw = <0x2>;
-			st,opp-default;
-		};
 	};
 };