am b76a63b7: vold: Change VFAT mount options to enable sdcard write restrictions

Merge commit 'b76a63b7bbdf8f51c4e689e241fca6d3a0bc1b1c'

* commit 'b76a63b7bbdf8f51c4e689e241fca6d3a0bc1b1c':
  vold: Change VFAT mount options to enable sdcard write restrictions