adjust parameter for factory SELinux setting

Bug: 171942789
Test: flash factory ROM with SELinux permissive
Change-Id: Iddbc758e562d4a97c82a16322c44af2e24d91ed1
diff --git a/factory_common.mk b/factory_common.mk
index 9872bc4..c8d0f58 100644
--- a/factory_common.mk
+++ b/factory_common.mk
@@ -51,7 +51,7 @@
 PRODUCT_DEFAULT_PROPERTY_OVERRIDES += ro.surface_flinger.use_content_detection_for_refresh_rate=true
 
 # factory should always has SELinux permissive
-BOARD_KERNEL_CMDLINE += androidboot.selinux=permissive
+BOARD_BOOTCONFIG += androidboot.selinux=permissive
 
 # Disable Bluetooth as default in factory build
 DEVICE_PACKAGE_OVERLAYS += device/google/gs101/overlay-factory