Object: Find terminator correctly when reading long filenames in GNU archives (PR37244)
Object: Find terminator correctly when reading long filenames in GNU archives (PR37244)

The code was previously relying on there being a null terminator
somewhere in (or after) the string table, something made less likely by
r330786.

Differential Revision: https://reviews.llvm.org/D46527

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@331746 91177308-0d34-0410-b5e6-96231b3b80d8

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