ARM: dts: STiH407-family: update rproc node names to avoid conflict

The two st231-rproc nodes have the same name; Due to that it was
impossible to distinguish them in remoteproc sysfs and debugfs
interface.
This patch provides them a name related to their functionality.
Signed-off-by: NLoic Pallardy <loic.pallardy@st.com>

arch/arm/boot/dts/stih407-family.dtsi

@@ -815,7 +815,7 @@
 			status		= "okay";
 		};
 
-		st231_gp0: remote-processor {
+		st231_gp0: st231-gp0@0 {
 			compatible	= "st,st231-rproc";
 			memory-region	= <&gp0_reserved>;
 			resets		= <&softreset STIH407_ST231_GP0_SOFTRESET>;
@@ -828,7 +828,7 @@
 			mboxes = <&mailbox0 0 2>, <&mailbox2 0 1>, <&mailbox0 0 3>, <&mailbox2 0 0>;
 		};
 
-		st231_delta: remote-processor {
+		st231_delta: st231-delta@0 {
 			compatible	= "st,st231-rproc";
 			memory-region	= <&delta_reserved>;
 			resets		= <&softreset STIH407_ST231_DMU_SOFTRESET>;