Update test to reflect the true section contents

Previously, LLVM object tools didn't know the true size of the sections.
This would result in tools thinking that a section with a VirtualSize
smaller than FileAlignment would end in zeros when actually those zeros
weren't really part of the section contents.

git-svn-id: https://llvm.org/svn/llvm-project/lld/trunk@219394 91177308-0d34-0410-b5e6-96231b3b80d8