[Chapel Merge] In the compiler, treat CHPL_LLVM=bundled like CHPL

Branch: refs/heads/master
Revision: 2b7fddc
Author: gbtitus
Log Message:

Merge pull request #16758 from gbtitus/compiler-CHPL_LLVM=bundled

In the compiler, treat CHPL_LLVM=bundled like CHPL_LLVM=llvm.

(Not reviewed. It’s late enough that nobody is around. Tonight’s
testing with LLVM will break without this, while with it I believe many
configs that failed last night will pass tonight. And it seems like a
simple enough change.)

This is more follow-up to the CHPL_xyz=bundled changes. Here, teach the
compiler that CHPL_LLVM=bundled means what CHPL_LLVM=llvm has meant in
the past.

Modified Files:
M compiler/llvm/clangUtil.cpp

Compare: https://github.com/chapel-lang/chapel/compare/2cfd3a5c9305...2b7fddc5a6d2