Add `--write-tix-file=<yes|no>` RTS option

Fixes #24002 (closed)

Open questions:

• In the RTS command line parser this is currently considered an OPTION_UNSAFE, since it influences behaviour which can overwrite files. But the default already generates a file, and this can be influenced by the (unguarded) environment variable HPCTIXFILE, and an executable compiled with -fhpc is probably not being used in a production environment. So declaring this option as OPTION_SAFE is an alternative.
• The haddock comments currently state @since 4.22.0.0 which should be correct if this lands in GHC 9.10