ARM cost model: Unaligned vectorized double stores are expensive

Updated a test case that assumed that <2 x double> would vectorize to use
<4 x float>.

radar://15338229

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193574 91177308-0d34-0410-b5e6-96231b3b80d8
3 files changed