Sort intrinsics by LLVM intrinsic name, rather than tablegen def name

Step one towards using a simple binary search to lookup intrinsic IDs
instead of our crazy table generated switch+memcmp+startswith code that
makes Function.cpp take about a minute to compile.  See PR24785 and
PR11951 for why we should do this.

The X86 backend contains tables that need to be sorted on intrinsic ID,
so reorder those.

llvm-svn: 258757