Specify a more specific triple for constant-pool-remat-0.ll

Instead of specifying 32-bit x86, specify 32-bit x86 linux.

This test is testing a very specific behavior which changed with
WinCOFF's constant pools.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213041 91177308-0d34-0410-b5e6-96231b3b80d8
Some targets don't prefix private symbols with dot

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213042 91177308-0d34-0410-b5e6-96231b3b80d8