[libcxx] Fixing silly mistake from last commit.

Tested on Linux x86_64 targeting Linux x86_64.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@256592 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/libcxx/test/target_info.py b/test/libcxx/test/target_info.py
index 927d7c5..bec8d98 100644
--- a/test/libcxx/test/target_info.py
+++ b/test/libcxx/test/target_info.py
@@ -142,7 +142,7 @@
             flags += ['-lunwind', '-ldl']
         else:
             flags += ['-lgcc_s', '-lgcc']
-        san = self.get_lit_conf('use_sanitizer', '').strip()
+        san = self.full_config.get_lit_conf('use_sanitizer', '').strip()
         if san:
             # The libraries and their order are taken from the
             # linkSanitizerRuntimeDeps function in