Merging r369097:

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r369097 | lewis-revill | 2019-08-16 14:00:56 +0200 (Fri, 16 Aug 2019) | 8 lines

[RISCV] Allow parsing of bare symbols with offsets

This patch allows symbols followed by an expression for an offset to be
parsed as bare symbols.

Differential Revision: https://reviews.llvm.org/D57332


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llvm-svn: 369338