GFS2: gfs2_edit fixes for 5.4
    
    bz 483799
    
    1. The ability for gfs2_edit to report on whether a given block is
       free, allocated data, or allocated metadata or unlinked metadata.
       This works on the interactive screen as well as -p blockalloc
       Values printed are: 0 (free), 1 (data), 2 (unlinked), 3 (meta).
    2. The ability for gfs2_edit to report on the metadata block type.
       Use: -p <block> blocktype
       Valid block types are: 0 (clump), 1 (superblock),
       2 (Resource Group Header), 3 (Resource Group Bitmap),
       4 (Dinode), 5 (Indirect Block), 6 (Directory Leaf),
       7 (Journaled Data), 8 (Log Header), 9 (Log descriptor),
       10 (Ext. attrib), 11 (Eattr Data), 12 (Log Buffer), 13 (invalid),
       14 (Quota Change).
    3. The ability for gfs2_edit to print out specific fields from
       a structure, such as an inode or rg.  -p <block> field <fieldname>
    4. The ability for gfs2_edit to edit the file system through the
       command line, like: -p <block> field <fieldname> <newval>
    5. The ability to search for blocks of a given metadata type, which
       is useful for digging through journals looking for evidence of
       something that's gone wrong.  In command-line mode, use:
       -p <block> find <sb|rg|rb|di|in|lf|jd|lh|ld|ea|ed|lb|13|qc>
       In interactive mode, change the block number to "/sb", "/rg", etc.
    6. The ability to edit fields in structure mode.  Right now, only
       dinode and rg structures are editable.  Others are ignored.
    7. Fixed a bug whereby -p size went on to print other things.
    8. The ability for gfs2_edit to print or change the metadata
       block type through the cli.  Use: -p <block> blocktype [newtype]
    9. The ability for gfs2_edit to locate which RG or bitmap block
       a certain block is associated with.  (i.e. locate the RG that's
       prior to the specified block).  For RG use: -p <block> blockrg
       For bitmaps use: -p <block> blockbits