Merging r371013:

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r371013 | ruiu | 2019-09-05 07:30:24 +0200 (Thu, 05 Sep 2019) | 13 lines

Align output segments correctly

Previously, segments were aligned according to their first section's
alignment requirements. That was not correct, but segments are also
aligned to a page boundary, and a page boundary is usually much larger
than a section alignment requirement, so no one noticed this bug before.

Now, lld has --nmagic option which sets maxPageSize to 1 to effectively
disable page alignment, which reveals the issue.

Fixes https://bugs.llvm.org/show_bug.cgi?id=43212

Differential Revision: https://reviews.llvm.org/D67152
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llvm-svn: 371197