Ensure __config_site definitions are passed to modules tests.

The test configuration contained a bug where we only raised
the __config_site commands to the command line if modules were
enabled for all of the libc++ tests. However there are special
modules-only tests, and these tests weren't getting the correct

This patch corrects that issue.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@367267 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed