package/busybox: write commented login line in /etc/inittab when getty disabled

When the "Run a getty" option is disabled, busybox doesn't remove the
/etc/inittab line from previous builds. With this patch, the line is
correctly commented out.

Signed-off-by: Stephen Bos <stephen.bos@hagergroup.com>
Co-authored-by: Stephen Bos <stephen.bos@hagergroup.com>
Co-authored-by: Christophe Blaess <christophe.blaess@logilin.fr>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

package/busybox/busybox.mk

@@ -218,8 +218,12 @@ define BUSYBOX_SET_GETTY
 	$(SED) '/# GENERIC_SERIAL$$/s~^.*#~$(SYSTEM_GETTY_PORT)::respawn:/sbin/getty -L $(SYSTEM_GETTY_OPTIONS) $(SYSTEM_GETTY_PORT) $(SYSTEM_GETTY_BAUDRATE) $(SYSTEM_GETTY_TERM) #~' \
 		$(TARGET_DIR)/etc/inittab
 endef
-BUSYBOX_TARGET_FINALIZE_HOOKS += BUSYBOX_SET_GETTY
+else
+define BUSYBOX_SET_GETTY
+	$(SED) '/# GENERIC_SERIAL$$/s~^.*#~#ttyS0::respawn:/sbin/getty -L ttyS0 115200 vt100 #~' $(TARGET_DIR)/etc/inittab
+endef
 endif # BR2_TARGET_GENERIC_GETTY
+BUSYBOX_TARGET_FINALIZE_HOOKS += BUSYBOX_SET_GETTY
 
 BUSYBOX_TARGET_FINALIZE_HOOKS += SYSTEM_REMOUNT_ROOT_INITTAB