[clang-query] Remove support for srcloc output (#92442)

This functionality was added about three years ago, but has been in a
significantly broken state since it was added. It has begun to cause a
maintenance burden for work in Clang (largely due to the complexity of
having two levels of code generation involved), and the original author
is unable to help maintain it. Because it only worked under limited
circumstances and because of the maintenance burden, it is being
removed. If someone wishes to resurrect the functionality, they should
hopefully be able to do so from this one commit.

Fixes #82591