[OpenMP] Remove 'unnecessary parentheses'

The variables in kmp_lock.cpp are really arrays of function pointers
that return void or int, not pointers to functions that return void*
or int*. The other changes are only cosmetic.

Differential Revision: https://reviews.llvm.org/D65870

git-svn-id: https://llvm.org/svn/llvm-project/openmp/trunk@369002 91177308-0d34-0410-b5e6-96231b3b80d8