boards: st: nucleo_wb07cc: enable RTC

Enable the RTC on Nucleo-WB07CC and update documentation accordingly.

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

Author: mathieuchopstm

boards/st/nucleo_wb07cc/nucleo_wb07cc.dts

@@ -66,6 +66,7 @@
 	};
 
 	aliases {
+		rtc = &rtc;
 		led0 = &blue_led_1;
 		led1 = &green_led_1;
 		led2 = &red_led_1;
@@ -104,6 +105,16 @@
 	slow-clock = <&clk_lse>;
 };
 
+&rtc {
+	/**
+	 * STM32_SRC_LSE reflects the "slow-clock" selected on RCC node.
+	 * NO_SEL reflects STM32WB0's lack of RTC clock mux to configure.
+	 */
+	clocks = <&rcc STM32_CLOCK(APB0, 12)>,
+		<&rcc STM32_SRC_LSE NO_SEL>;
+	status = "okay";
+};
+
 &bt_hci_wb0 {
 	status = "okay";
 };

boards/st/nucleo_wb07cc/nucleo_wb07cc.yaml

@@ -16,6 +16,7 @@ supported:
   - gpio
   - i2c
   - pwm
+  - rtc
   - spi
   - bluetooth
 vendor: st