Don't check fs modified when dump target is lvm2 thinp
    
    upstream: fedora
    resolves: bz2083475
    conflict: none
    
    commit 3ae8cf8876edd6ca668890f55d4c006e28a41f90
    Author: Tao Liu <ltao@redhat.com>
    Date:   Thu Nov 10 10:25:58 2022 +0800
    
        Don't check fs modified when dump target is lvm2 thinp
    
        When the dump target is lvm2 thinp, if we didn't mount
        the dump target first, get_fs_type_from_target will get
        empty output:
    
        Before mount:
        $ get_fs_type_from_target /dev/vg00/thinlv
    
        After mount:
        $ mount /dev/vg00/thinlv /mnt
        $ get_fs_type_from_target /dev/vg00/thinlv
        ext4
    
        As a result, kdumpctl start will fail with:
        $ kdumpctl start
        kdump: Dump target is invalid
        kdump: Starting kdump: [FAILED]
    
        This patch fix the issue by bypassing check_fs_modified
        when the dump target is lvm2 thinp.
    
        Signed-off-by: Tao Liu <ltao@redhat.com>
        Reviewed-by: Coiby Xu <prudo@redhat.com>
    
    Signed-off-by: Tao Liu <ltao@redhat.com>