[llvm] [BOLT][NFC] Added double escape characters (PR #93348)

[David Blaikie via llvm-commits]

dwblaikie wrote:

(personally - I'm not sure if this convention is really a great one, especially unsure whether it's worthwhile mass-migrating code to use it... (seems like it's pretty close to other broad formatting changes which we don't usually apply broadly) - before any of these patches go in, maybe worth a discourse thread?)

https://github.com/llvm/llvm-project/pull/93348