[WebAssembly] Cleanup unused declares in test code. NFC.

In one case probably you have be using it, in the other it
looks like it was redundant.

Differential Revision: https://reviews.llvm.org/D54644

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@347098 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed