[clang] [clang] Add GCC-compatible code model names for sparc64 (PR #79485)

[Rainer Orth via cfe-commits]

rorth wrote:

GCC also supports `-mcmodel=embmedany`.  Maybe it would be good to reject that with a clear message?

As for the generated code (not this PR, I'd say), it would certainly be good to test that on some larger code base (like LLVM itself) and, preferably, also test actual interoperability with GCC. Especially in SPARC support, I have seen to many cases where LLVM wouldn't interoperate with itself, let alone GCC.

https://github.com/llvm/llvm-project/pull/79485