pdbg: Bump to v2.0

Alistair Popple (1):
      Bump version to 2.0

Amitay Isaacs (3):
      script: Mark dtb pointers as extern
      build: Add explicit dependency of libfdt for libpdbg
      generate_dt_header: Fix typo

(From meta-openpower rev: 354ee8d443f15f9716f04ff3390abb8a69bd3f66)

Change-Id: Iecdee14b91332d62fafee40cdcd11773ca369125
Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>