zenfone9: Add BOARD_MOVE_GSI_AVB_KEYS_TO_VENDOR_BOOT flag

Change-Id: I9d4b95dfa040db98e3805ce9689c6ba73d97cb44
diff --git a/BoardConfig.mk b/BoardConfig.mk
index 638a29b..2f47452 100755
--- a/BoardConfig.mk
+++ b/BoardConfig.mk
@@ -154,6 +154,8 @@
     HOSTCFLAGS="-fuse-ld=lld -Wno-unused-command-line-argument"
 TARGET_KERNEL_ADDITIONAL_FLAGS += LLVM=1 LLVM_IAS=1
 
+BOARD_MOVE_GSI_AVB_KEYS_TO_VENDOR_BOOT := true
+
 # NFC
 TARGET_USES_NQ_NFC := true