[llvm-profdata] Profile dump for compact binary format

Summary: Fix "llvm-profdata show" so it can work with compact binary format profile. The change is to mark all functions "used" so SampleProfileReaderCompactBinary::read will read in all profiles available for dumping. The function names will be MD5 hash for compact binary format.

Reviewers: wmi, davidxl, danielcdh

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65162

llvm-svn: 368731