[llvm-config] Fix cflags test looking for "warning"
This will fail if you configure with e.g. -Wno-unknown-warning-option.
Change it to check for 'warning:' just like we did for 'error:' in
r289484.
llvm-svn: 304239
diff --git a/llvm/test/tools/llvm-config/cflags.test b/llvm/test/tools/llvm-config/cflags.test
index ef3e486..461de86 100644
--- a/llvm/test/tools/llvm-config/cflags.test
+++ b/llvm/test/tools/llvm-config/cflags.test
@@ -4,4 +4,4 @@
CHECK: -I
CHECK: {{[/\\]}}include
CHECK-NOT: error:
-CHECK-NOT: warning
+CHECK-NOT: warning: