test: Use $SharedLibDir for loadable modules. On Cygming, loadable modules are not in lib/ but bin.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120274 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/lit.cfg b/test/lit.cfg
index aa1e1a9..63b0032 100644
--- a/test/lit.cfg
+++ b/test/lit.cfg
@@ -128,6 +128,7 @@
 config.substitutions.append(('%llvmgcc_only', site_exp['llvmgcc']))
 for sub in ['llvmgcc', 'llvmgxx', 'emitir', 'compile_cxx', 'compile_c',
             'link', 'shlibext', 'ocamlopt', 'llvmdsymutil', 'llvmlibsdir',
+            'llvmshlibdir',
             'bugpoint_topts']:
     if sub in ('llvmgcc', 'llvmgxx'):
         config.substitutions.append(('%' + sub,