Fix Incorrect CHECK message [0-31]+ in test case.
In regular expression, [0-31]+ equals to [0-3]+, not the number from
0 to 31. So change it to [0-9]+.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197113 91177308-0d34-0410-b5e6-96231b3b80d8