BMC update via TFTP

[Gunnar Mills]

> In BMC WebUI under "Download image file from TFTP server" section,
> we have text fields "TFTP Server IP address" and "File name".
> "File name" doesn't take folders in path. Is this a bug or expected 
> behavior?
>
> TFTP downloads work only if file is kept in root of tftp share.
>
This is expected.
https://github.com/openbmc/phosphor-bmc-code-mgmt/blob/b0ce996ac60cf80487d71c3cdb7165d065079377/download_manager.cpp#L33