It turns out that people love using VLAs in templates, too. Weaken our
VLA restrictions so that one can use VLAs in templates (even
accidentally), but not as part of a non-type template parameter (which
would be very bad).


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@104471 91177308-0d34-0410-b5e6-96231b3b80d8