src: fix compiler warning in udp_wrap.cc

Currently the following compiler warning is generated:

1 warning generated.
../src/udp_wrap.cc:238:12: warning: comparison of integers of different
signs: 'int' and 'uint32_t' (aka 'unsigned int') [-Wsign-compare]
  if (size != args[0].As<Uint32>()->Value()) {
      ~~~~ ^  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1 warning generated.

This commit changes the check to see that the Uint32 value does not exceed the max int size instead of first casting and then comparing.

Checklist

• make -j4 test (UNIX), or vcbuild test (Windows) passes
• commit message follows commit guidelines

Affected core subsystem(s)

src