54aadcd5d1
Replace all of calls of `format()` with `formatv()` in
`DWARFVerifier.cpp`. Also use `formatv()` when strings were concatenated
with `+` or streamed with `<<`.
See
[llvm/include/llvm/Support/FormatProviders.h](2f3935bcee/llvm/include/llvm/Support/FormatProviders.h (L96-L117))
for the hexadecimal grammar. e.g. `x+` to print the `0x` prefix or `x-`
to not print it.
My motivation is to:
1. make it easier to read the format strings and
2. have less `formatv()` calls when it was used on arguments to the
format string before.
Relates to #35980