test: Fix match string to work with st0 or stmm0


git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@196919 91177308-0d34-0410-b5e6-96231b3b80d8
test: FreeBSD calls the 64-bit x86 platform amd64

Also add decorator for an issue that this uncovered: llvm.org/pr18200


git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@196920 91177308-0d34-0410-b5e6-96231b3b80d8