Update git submodules

* Update docs/submodules/so.git from branch 'master'
  to 638880aec2c0a21505720a204bd9ae0fcc83608c
  - SDNC request body fix
    
    Request body fix for sdnc requests.
    
    Change-Id: Id3e454be18c62ab8c2e5ee572de55bf3ef7c18a3
    Issue-ID: SO-1393
    Signed-off-by: subhash kumar singh <subhash.kumar.singh@huawei.com>
    
1 file changed