[clang] [Headers][X86] Add specific results to comparisons (PR #83316)

[Simon Pilgrim via cfe-commits]

RKSimon wrote:

@pogo This doesn't match what we did for the various cmp intrinsics in emmintrin.h - should it?
```cpp
/// Compares each of the corresponding signed 32-bit values of the
///    128-bit integer vectors to determine if the values in the first operand
///    are greater than those in the second operand.
///
///    Each comparison yields 0x0 for false, 0xFFFFFFFF for true.
///
/// \headerfile <x86intrin.h>
///
/// This intrinsic corresponds to the <c> VPCMPGTD / PCMPGTD </c> instruction.
```

https://github.com/llvm/llvm-project/pull/83316