llvm-config: Default to "all" if no components are specified.

- Fixes PR11530.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@146388 91177308-0d34-0410-b5e6-96231b3b80d8

tools/llvm-config/llvm-config.cpp

@@ -300,6 +300,10 @@ int main(int argc, char **argv) {
     usage();
 
   if (PrintLibs || PrintLibNames || PrintLibFiles) {
+    // If no components were specified, default to "all".
+    if (Components.empty())
+      Components.push_back("all");
+
     // Construct the list of all the required libraries.
     std::vector<StringRef> RequiredLibs;
     ComputeLibsForComponents(Components, RequiredLibs);