feat: add fp16 to V8 deps (#775)

Refs: v8/v8@6196de8
Refs: v8/v8@8fcd3f8

Author: targos

lib/update-v8/constants.js

@@ -34,6 +34,10 @@ const abseilIgnore = `!/third_party/abseil-cpp
 /third_party/abseil-cpp/.github
 /third_party/abseil-cpp/ci`;
 
+const fp16Ignore = `!/third_party/fp16
+/third_party/fp16/src/*
+!/third_party/fp16/src/include`;
+
 export const v8Deps = [
   {
     name: 'trace_event',
@@ -92,5 +96,11 @@ export const v8Deps = [
     repo: 'third_party/abseil-cpp',
     gitignore: abseilIgnore,
     since: 121
+  },
+  {
+    name: 'fp16',
+    repo: 'third_party/fp16/src',
+    gitignore: fp16Ignore,
+    since: 124
   }
 ];