zenfone6: device cleanup

Change-Id: Ic499184bd78a678fad971a79feac1ff2c58bf9dc
diff --git a/BoardConfig.mk b/BoardConfig.mk
index ce603ec..05d19a4 100755
--- a/BoardConfig.mk
+++ b/BoardConfig.mk
@@ -47,7 +47,7 @@
 TARGET_NO_BOOTLOADER := true
 
 # A/B
-BOARD_AVB_MAKE_VBMETA_IMAGE_ARGS += --set_hashtree_disabled_flag
+BOARD_AVB_ENABLE := true
 BOARD_AVB_MAKE_VBMETA_IMAGE_ARGS += --flags 2
 
 # ANT+
@@ -110,14 +110,12 @@
 BOARD_TAGS_OFFSET := 0x00000100
 TARGET_KERNEL_ARCH := arm64
 TARGET_KERNEL_HEADER_ARCH := arm64
-#TARGET_KERNEL_CROSS_COMPILE_PREFIX := aarch64-linux-android-
 BOARD_KERNEL_IMAGE_NAME := Image.gz-dtb
 TARGET_COMPILE_WITH_MSM_KERNEL := true
 TARGET_KERNEL_SOURCE := kernel/asus/sm8150
 TARGET_KERNEL_CONFIG := vendor/zs630kl_defconfig
 BOARD_KERNEL_SEPARATED_DTBO := true
 TARGET_KERNEL_CLANG_COMPILE := true
-TARGET_KERNEL_CLANG_VERSION := 7.0.2
 
 # Modules
 NEED_KERNEL_MODULE_SYSTEM := true
@@ -129,8 +127,6 @@
 TARGET_OTA_ASSERT_DEVICE := WW_I01WD
 
 # Partitions
-BOARD_AVB_ENABLE := true
-BOARD_AVB_ROLLBACK_INDEX := $(PLATFORM_SECURITY_PATCH_TIMESTAMP)
 BOARD_BUILD_SYSTEM_ROOT_IMAGE := true
 BOARD_BOOTIMAGE_PARTITION_SIZE := 100663296
 BOARD_DTBOIMG_PARTITION_SIZE := 8388608