[XRay] rm GLOB || true -> rm -f

Summary: `rm -f` does not write diagnostic message when there is no file argument.

Reviewers: dberris

Subscribers: delcypher, llvm-commits, #sanitizers

Differential Revision: https://reviews.llvm.org/D48311

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@335025 91177308-0d34-0410-b5e6-96231b3b80d8
12 files changed