Use clang intrinsic for quic for Windows ARM64

The intrinsic _mm_prefetch on Windows is x86/x64 only. Instead select
__builtin_prefetch from clang for Windows ARM64.

Bug: 893460
Change-Id: I484b13fe7c616b52abe4b1dff06a5f830fd538d2
Reviewed-on: https://chromium-review.googlesource.com/c/1292528Reviewed-by: Bruce Dawson <brucedawson@chromium.org>
Reviewed-by: Asanka Herath <asanka@chromium.org>
Commit-Queue: Bruce Dawson <brucedawson@chromium.org>
Cr-Commit-Position: refs/heads/master@{#601335}

net/third_party/quic/platform/impl/quic_prefetch_impl.h

@@ -12,7 +12,7 @@
 namespace quic {
 
 inline void QuicPrefetchT0Impl(const void* addr) {
-#if defined(__GNUC__)
+#if defined(__GNUC__) || (defined(_M_ARM64) && defined(__clang__))
   __builtin_prefetch(addr, 0, 3);
 #elif defined(_MSC_VER)
   _mm_prefetch(reinterpret_cast<const char*>(addr), _MM_HINT_T0);