dts: st: stm32f100: add correct 'v25' property on die temp sensor

The typical value for V25 is different on the STM32F100 line compared
to other STM32F1 MCUs. Update the DTS property to the correct value.

Signed-off-by: Mathieu Choplain <mathieu.choplain@st.com>

dts/arm/st/f1/stm32f100Xb.dtsi

@@ -52,4 +52,8 @@
 			#io-channel-cells = <1>;
 		};
 	};
+
+	die_temp: dietemp {
+		v25 = <1410>;
+	};
 };