[ubsan] Use the correct tool name in diagnostics

When using ASan and UBSan together, the common sanitizer tool name is
set to "AddressSanitizer". That means that when a UBSan diagnostic is
printed out, it looks like this:

  SUMMARY: AddressSanitizer: ...

This can confuse users. Fix it so that we always use the correct tool
name when printing out UBSan diagnostics.

Differential Revision: https://reviews.llvm.org/D32066

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@300358 91177308-0d34-0410-b5e6-96231b3b80d8
(cherry picked from commit 6d4c217ce48343d72a68f328f792d5bab487f192)
7 files changed