i#1870: Support ordinal forwarders (#3221)
i#1870: Support ordinal forwarders (#3221)

Adds support for ordinal forwarders, and fixes a sanity check to
handle DLLs that contain no named exports.

Fixes #1870
AmesianX/dynamorio,AmesianX/dynamorio,AmesianX/dynamorio,AmesianX/dynamorio,AmesianX/dynamorio