Remove dead host_pdr_handler code & json-file

The content from host_fru.json is being parsed and parents map is being
populated with that data, but the parents map isn't being used anywhere
in the code base making it a dead code, so removing the json file & also
the code that parses it.

This part of code was once added to normalize the PDR's, but now we have
a better/efficient/dynamic way to normalize the PDR's which does not
need any JSON files & static configuration.So we don't need this code
anymore.

Tested:
Code builds & unit tests are passed.

Change-Id: I3c9af49ef3644c08d80e207b86614de1b5b919c2
Signed-off-by: Manojkiran Eda <manojkiran.eda@gmail.com>