[clang] [Clang] Add __builtin_bswapg (PR #162433)

[Aaron Ballman via cfe-commits]

================
@@ -281,6 +281,10 @@ Non-comprehensive list of changes in this release
   allocator-level heap organization strategies. A feature to instrument all
   allocation functions with a token ID can be enabled via the
   ``-fsanitize=alloc-token`` flag.
+ 
+- A new generic byte swap builtin function ``__builtin_bswapg`` that extends the existing 
----------------
AaronBallman wrote:

Why the `g` in the name instead of just `__builtin_bswap`?

https://github.com/llvm/llvm-project/pull/162433