deps: cherry-pick win/arm64/clang fix for nghttp3

Refs: ngtcp2/nghttp3#112

Author: zcbenz

deps/ngtcp2/nghttp3/lib/nghttp3_ringbuf.c

@@ -33,7 +33,7 @@
 
 #include "nghttp3_macro.h"
 
-#if defined(_MSC_VER) && defined(_M_ARM64)
+#if defined(_MSC_VER) && !defined(__clang__) && (defined(_M_ARM) || defined(_M_ARM64))
 unsigned int __popcnt(unsigned int x) {
   unsigned int c = 0;
   for (; x; ++c) {