[clang] [clang][test] Fix builtin-rotate.c failure on ARM32 by adding x86_64 triple (PR #177290)

[Simon Pilgrim via cfe-commits]

RKSimon wrote:

builtinsc.c uses a `#ifdef __SIZEOF_INT128__` guard - not sure if thats the preferred workaround though

https://github.com/llvm/llvm-project/pull/177290