m20lte: Symlink /mnt/vendor/efs to /efs

 * follow stock behaviour
 * liboemcrypto is looking for wv.keys in /efs instead of /mnt/vendor/efs

Change-Id: I4ee4a4818dbd91285fcfeb4450b3124cf1ca6607
Signed-off-by: SamarV-121 <samarvispute121@pm.me>
diff --git a/BoardConfig.mk b/BoardConfig.mk
index 604dba5..1cce3db 100644
--- a/BoardConfig.mk
+++ b/BoardConfig.mk
@@ -16,6 +16,8 @@
 BOARD_SYSTEMIMAGE_PARTITION_SIZE := 3565158400
 BOARD_RECOVERYIMAGE_PARTITION_SIZE := 39845888
 
+BOARD_ROOT_EXTRA_SYMLINKS := /mnt/vendor/efs:/efs
+
 # Recovery
 TARGET_RECOVERY_FSTAB := $(DEVICE_PATH)/rootdir/etc/fstab.exynos7904