swr: fix llvm-5.0.0 build bustage
swr: fix llvm-5.0.0 build bustage

Handle rename of llvm AttributeSet to AttributeList in the same
fashion as ac_llvm_helper.cpp.

Reviewed-by: Bruce Cherniak <a5345730962d952f474b19e983398300e1cb5f29@intel.com>

metora/MesaGLSLCompiler,metora/MesaGLSLCompiler,metora/MesaGLSLCompiler