Resolve conflicts in pg_backup.h, pg_backup_db.c, and pg_backup_archiver.c

[RekGRpth]

1. Commit a45bc8a in src/bin/pg_dump/pg_backup.h added the definition
   of the new ConnParams structure, while earlier commit 3040b44 had
   already done the same, adding the definition of the new
   _dumpPreparedQueries enumeration above.

2. Commit a45bc8a in src/bin/pg_dump/pg_backup.h changed the arguments
   in the ConnectDatabase function definition, while earlier commit
   19cd1cf had already added the new bool binary_upgrade argument.

3. Commit 257836a added a new field, coll_unknown, to the DumpOptions
   structure in src/bin/pg_dump/pg_backup.h, while an earlier commit,
   77cd915, had already added the GPDB-specific fields, dumpGpPolicy and
   isGPbackend, in the same location.

4. Commit a45bc8a removed the declaration of the _connectDB function in
   src/bin/pg_dump/pg_backup_db.c, while an earlier commit, 8ae22d1,
   had already added pg_attribute_unused to the notice_processor function
   argument below.

5. Commit a45bc8a in src/bin/pg_dump/pg_backup_db.c refactored the
   code, including arguments, in the ConnectDatabase function. However,
   the earlier commit 19cd1cf had already added the new bool
   binary_upgrade argument and its handling.

6. Commit a45bc8a in src/bin/pg_dump/pg_backup_archiver.c in the
   RestoreArchive function changed the call to the ConnectDatabase
   function. However, the earlier commit 19cd1cf had already added the new
   bool binary_upgrade argument to the ConnectDatabase function.

7. Commit a45bc8a in src/bin/pg_dump/pg_backup_archiver.c changed the
   call to the ConnectDatabase function in the
   restore_toc_entries_postfork function, while the earlier commit 19cd1cf
   had already added a new bool binary_upgrade argument to the
   ConnectDatabase function.

8. Commit a45bc8a in src/bin/pg_dump/pg_backup_archiver.c simplified
   the code in the CloneArchive function, while the earlier commit 19cd1cf
   had already added a new bool binary_upgrade argument to the
   ConnectDatabase function.