boards: nrf5340_dk_nrf5340: enable ECC if building with BT

When building with support for BLE stack, enable the BT_ECC
for the nRF5340 NET CPU (Network MCU).

Signed-off-by: Kamil Piszczek <[email protected]>

Author: kapi-no

boards/arm/nrf5340_dk_nrf5340/Kconfig

@@ -32,4 +32,7 @@ if BOARD_NRF5340_DK_NRF5340_CPUNET
 config BT_CTLR
 	default y if BT
 
+config BT_ECC
+	default y if BT
+
 endif # BOARD_NRF5340_DK_NRF5340_CPUNET