Add eraseblk and logicalblk fs_mgr flags

When doing a factory reset in recovery, flash erase & logical block
sizes are needed for tuning the parameters of the new userdata image.
Add flags to allow this information to be stored in recovery.fstab

Test: Factory reset marlin & confirm userdata is rebuilt correctly
Bug: 33243520
Change-Id: I6c4414d4e9026be4a3646523656ac151e93015e7
Signed-off-by: Connor O'Brien <connoro@google.com>