[Clang] Add options -fprofile-filter-files and -fprofile-exclude-files to...

[Clang] Add options -fprofile-filter-files and -fprofile-exclude-files to filter the files to instrument with gcov

Summary:
These options are taking regex separated by colons to filter files.
- if both are empty then all files are instrumented
- if -fprofile-filter-files is empty then all the filenames matching any of the regex from exclude are not instrumented
- if -fprofile-exclude-files is empty then all the filenames matching any of the regex from filter are instrumented
- if both aren't empty then all the filenames which match any of the regex in filter and which don't match all the regex in filter are instrumented
- this patch is a follow-up of https://reviews.llvm.org/D52033

Reviewers: marco-c, vsk

Reviewed By: marco-c, vsk

Subscribers: cfe-commits, sylvestre.ledru

Differential Revision: https://reviews.llvm.org/D52034

llvm-svn: 346642