boards: shields: x_nucleo_idb05a1: '-' is not an allowed nodelabel char

When adding nodelabels to shields devices, it should be taken car not to
use forbidden characters.
Fix existing occurrence.

Signed-off-by: Erwan Gouriou <[email protected]>

Author: erwango

boards/shields/x_nucleo_idb05a1/boards/stm32mp157c_dk2.overlay

@@ -5,7 +5,7 @@
  */
 
 &arduino_spi {
-	spbtle-rf_x_nucleo_idb05a1: spbtle-rf@0 {
+	spbtle_rf_x_nucleo_idb05a1: spbtle-rf@0 {
 		cs-gpios = <&arduino_header 16 (GPIO_ACTIVE_HIGH | GPIO_PULL_UP)>;	      /* D10 */
 		irq-gpios = <&arduino_header 15 0>;	 /* D9 */
 	};

boards/shields/x_nucleo_idb05a1/x_nucleo_idb05a1.overlay

@@ -7,7 +7,7 @@
 &arduino_spi {
 	cs-gpios = <&arduino_header 1 (GPIO_ACTIVE_HIGH | GPIO_PULL_UP)>;	      /* A1 */
 
-	spbtle-rf_x_nucleo_idb05a1: spbtle-rf@0 {
+	spbtle_rf_x_nucleo_idb05a1: spbtle-rf@0 {
 		compatible = "zephyr,bt-hci-spi";
 		reg = <0>;
 		reset-gpios = <&arduino_header 13 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>; /* D7 */