openpower:dreport: add PHAL device tree debug data to BMC dump

1. Generate attribute list to a file and append the file to
the dump.

2. Append the device tree blob file to the dump

3. Append export device tree file to the dump

4. Append attributes_info.db file to the dump

Tested
root@ever8bmc:/tmp/test/obmcdump_00000000_1648657576# ls -lah DEVTREE
-r--r-----    1 root     root      840.0K Mar 30 16:26 DEVTREE
root@ever8bmc:/tmp/test/obmcdump_00000000_1648657576# ls -lah attributes_info.db
-rw-r--r--    1 root     root       10.4K Mar 30 16:26 attributes_info.db
root@ever8bmc:/tmp/test/obmcdump_00000000_1648657576# ls -lah PHAL_devtree.txt
-rw-r--r--    1 root     root        2.2M Mar 30 16:26 PHAL_devtree.txt

Signed-off-by: Marri Devender Rao <devenrao@in.ibm.com>
Change-Id: I3b60f136e04be2ed44349c9c91fe3858dd78a91a