[nrf noup] boot: zephyr: serial_recovery: Allow GPIO usage in BM

Allows GPIO entrance mode when bare metal is used, this is needed
because the zephyr GPIO drivers are not used, therefore the Kconfig
will not be enabled

Signed-off-by: Jamie McCrae <jamie.mccrae@nordicsemi.no>

Author: nordicjm

boot/zephyr/Kconfig.serial_recovery

@@ -142,7 +142,7 @@ menu "Entrance methods"
 menuconfig BOOT_SERIAL_ENTRANCE_GPIO
 	bool "GPIO"
 	default y
-	depends on GPIO
+	depends on GPIO || NCS_BM
 	help
 	  Use a GPIO to enter serial recovery mode.