Revert "Set block device as RO/RW before mount"

This reverts commit c6dfdbb7.

Reason for revert: Likely culprit for b/356319388  - verifying through ABTD before revert submission. This is part of the standard investigation process, and does not mean your CL will be reverted.

Change-Id: Ibd85b26a02f0278676f330c6825d3cb15eefe3fc