zenfone6: override fstab.qcom from vendor to remove wrappedkey

* Asus has `wrappedkey` enabled in their fstab but actually does not
use it at all. To match this, we have to override the fstab by
bind-mounting.
diff --git a/recovery.fstab b/recovery.fstab
index 91ae9dd..94ae853 100644
--- a/recovery.fstab
+++ b/recovery.fstab
@@ -8,7 +8,7 @@
 #<src>                                                 <mnt_point>            <type>  <mnt_flags and options>                            <fs_mgr_flags>
 /dev/block/bootdevice/by-name/system                    /                      ext4    ro,barrier=1,discard                                 wait,slotselect,avb
 /dev/block/bootdevice/by-name/metadata                  /metadata              ext4    noatime,nosuid,nodev,discard                         wait,formattable
-/dev/block/bootdevice/by-name/userdata                  /data                  f2fs     noatime,nosuid,nodev,discard,nobarrier        latemount,wait,check,fileencryption=ice,wrappedkey,keydirectory=/metadata/vold/metadata_encryption,quota,reservedsize=128M
+/dev/block/bootdevice/by-name/userdata                  /data                  f2fs     noatime,nosuid,nodev,discard,nobarrier        latemount,wait,check,fileencryption=ice,keydirectory=/metadata/vold/metadata_encryption,quota,reservedsize=128M
 /dev/block/bootdevice/by-name/persist                   /mnt/vendor/persist    ext4    noatime,nosuid,nodev,barrier=1                       wait
 /dev/block/bootdevice/by-name/modem                     /vendor/firmware_mnt   vfat    ro,shortname=lower,uid=0,gid=1000,dmask=227,fmask=337,context=u:object_r:firmware_file:s0 wait,slotselect
 /dev/block/bootdevice/by-name/dsp                       /vendor/dsp            ext4    ro,nosuid,nodev,barrier=1                            wait,slotselect