[llvm-cov] - Add the coverage of lines in the summary report.

The llvm-cov ‘report' command displays a summary of the coverage of a binary file.
The summary report currently only includes covered regions and covered functions.
This patch adds the coverage of lines in the summary report.

Differential Revision: https://reviews.llvm.org/D22569

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@276409 91177308-0d34-0410-b5e6-96231b3b80d8
3 files changed