Specify checksums properly for llgs test suite packets.

Summary: These checksums are ignored by llgs but some implementations require them to be specified properly.

Test Plan: Re-run llgs tests with the checksums and make sure we don't break anything.

Reviewers: tfiala, clayborg

Subscribers: lldb-commits

Differential Revision: http://reviews.llvm.org/D6254

git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@221927 91177308-0d34-0410-b5e6-96231b3b80d8