Merging r366500:

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r366500 | quantum | 2019-07-18 23:18:24 +0200 (Thu, 18 Jul 2019) | 13 lines

[WebAssembly] fix bug in finding .tdata segment

Summary: Fix bug in `wasm-ld`'s `Writer::createInitTLSFunction` that only finds `.tdata` if it's the first section.

Reviewers: tlively, aheejin, sbc100

Reviewed By: sbc100

Subscribers: dschuff, jgravelle-google, sunfish, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D64947
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llvm-svn: 366707