[BOLT] Fix getNewValueForSymbol()

Summary:
getNewValueForSymbol() uses orc::RTDyldObjectLinkingLayer::findSymbol()
to resolve symbol values. The latter will always return JITSymbol,
even if there was no symbol defined. The address for the undefined
symbol will be zero, but some symbols could legally be resolved to zero
too.

We need to distinguish between real zero-valued symbols and symbols that
were not emitted and are not visible by orc::RTDyldObjectLinkingLayer.
If zero address is returned by ORC, check for a binary data with the
same name and use its address for the symbol resolution.

(cherry picked from FBD22175269)