[clang] [llvm] Fix Windows EH IP2State tables (remove +1 bias) (PR #144745)

[via llvm-commits]

dyung wrote:

> This is causing failures on my macOS machine that uses paths starting with "/Users":

These test failures also appeared on my macOS bot: https://lab.llvm.org/buildbot/#/builders/190/builds/23983

https://github.com/llvm/llvm-project/pull/144745