[MERGE #4322 @notvita] Win: Fix undefined uint16_t (issue #4320)
[MERGE #4322 @notvita] Win: Fix undefined uint16_t (issue #4320)

Merge pull request #4322 from notvita:undefined-uint16_t

uint16_t would be undefined when using a Visual C++ compiler higher than version 1900, include stdint.h if that is the case.

[Issue #4320](https://github.com/Microsoft/ChakraCore/issues/4320)

Microsoft/ChakraCore,Microsoft/ChakraCore,mrkmarron/ChakraCore,mrkmarron/ChakraCore,Microsoft/ChakraCore,mrkmarron/ChakraCore,mrkmarron/ChakraCore,Microsoft/ChakraCore,mrkmarron/ChakraCore,mrkmarron/ChakraCore,Microsoft/ChakraCore,mrkmarron/ChakraCore,Microsoft/ChakraCore