process bounds expressions for parameters with all the parameters available

[secure-sw-dev-bot]

This issue was copied from checkedc/checkedc-clang#7

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Bounds expressions need to processed during clang's semantic checking/processing phase in a scope with all the parameters available. I am about to submit a pull request where they are being processed in a scope that contains only the parameters seen so far.

This is a little complicated to implement in clang's semantic checking/processing phase. You have to delay parsing of the bounds expressions because parsing and semantic processing are intermixed.

[secure-sw-dev-bot]

Comment from @dtarditi:

This work is complete.