[clang-tidy] Remove unnecessary getName() on Decls and Types feeding into a DiagnosticBuilder

Going through a string removes some of the smarts of the diagnosic printer
and makes the code more complicated. This change has some cosmetic impact
on the output but that's mostly minor.

git-svn-id: https://llvm.org/svn/llvm-project/clang-tools-extra/trunk@265680 91177308-0d34-0410-b5e6-96231b3b80d8
12 files changed