Bug 2131948

This bug was initially created as a copy of Bug #2131946

I am copying this bug because: 

Also happens with rear-2.4-16.el7_9.
Prevents unattended restore (when automatic mapping happens).

Description of problem:

The issue happens when having the following conditions:
1. Non-LVM XFS filesystem is restored (e.g. `/boot`)
2. XFS filesystem has `sunit!=0` and `swidth!=0`
3. Disk mapping occurs (e.g. vda -> vdb)

When all three conditions are met, ReaR creates the file system with default settings because of the absence of `/var/lib/rear/layout/xfs/vda1.xfs` file, resulting in using default options to XFS when creating the filesystem:
~~~
2022-10-04 09:19:32.261221631 Can't read /var/lib/rear/layout/xfs/vdb1.xfs, falling back to mkfs.xfs defaults.
...
+++ mkfs.xfs -f -m uuid=17c2c80a-afad-4b64-a31b-55b21ced3740 /dev/vdb1
meta-data=/dev/vdb1              isize=512    agcount=4, agsize=65536 blks
         =                       sectsz=512   attr=2, projid32bit=1
         =                       crc=1        finobt=1, sparse=1, rmapbt=0
         =                       reflink=1    bigtime=0 inobtcount=0
data     =                       bsize=4096   blocks=262144, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0, ftype=1
log      =internal log           bsize=4096   blocks=2560, version=2
         =                       sectsz=512   sunit=0 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0
~~~

Later, ReaR mounts the filesystem with XFS specific options (`sunit=xxx,swidth=xxx`) which are incompatible (due to having use default options at file system creation time) and this fails:
~~~
+++ mount -o rw,relatime,attr2,inode64,logbufs=8,logbsize=256k,sunit=512,swidth=512,noquota /dev/vdb1 /mnt/local/boot
mount: /mnt/local/boot: wrong fs type, bad option, bad superblock on /dev/vdb1, missing codepage or helper program, or other error.
~~~

This was fixed in ReaR Upstream through commit a8fd431fda6c47ee5d1f4e24065bc28280a1f46d.

Version-Release number of selected component (if applicable):

rear-2.6-4.el8

How reproducible:

Always

Steps to Reproduce:
1. Make sure `/boot` is not using defaults `sunit=0` settings

    ~~~
    # BOOT_DEV=$(findmnt -o source --noheadings /boot)
    # BOOT_UUID=$(blkid -s UUID -o value $BOOT_DEV)
    # tar cf /root/boot.tar -C /boot .
    # umount /boot
    # mkfs.xfs -f -m uuid=$BOOT_UUID -d sunit=512,swidth=512 $BOOT_DEV
    # mount /boot
    # tar xf /root/boot.tar -C /boot
    ~~~

2. Create the rescue

3. Add a disk with same size (to force migration mode)

4. Boot on rescue and recover on other disk after wiping the disks (to avoid duplicates)

    ~~~
    # wipefs -a /dev/vda
    # wipefs -a /dev/vdb
    # rear recover
    ...
    Current disk mapping table (source => target):
      /dev/vda => /dev/vda
    ...
    3) Edit disk mapping (/var/lib/rear/layout/disk_mappings)
    4) Use Relax-and-Recover shell and return back to here
    5) Abort 'rear recover'
    (default '1' timeout 300 seconds)
    3
    
      /dev/vda /dev/vdb
    ...
    ~~~

Actual results:

Failure mounting `/boot`

Expected results:

No failure + proper XFS options used