fstab.common: Mount external usb storage am: c98a9afbc5 am: de827eb203

Original change: https://android-review.googlesource.com/c/device/linaro/dragonboard/+/2875514

Change-Id: Iecd9bcd83e3b3010034c03d41bc249d5c52c111d
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>