Improving the name of the function parameter, which happens to solve two likely-less-than-useful MSVC warnings: warning C4258: 'I' : definition from the for loop is ignored; the definition from the enclosing scope is used.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214717 91177308-0d34-0410-b5e6-96231b3b80d8