Add AIStateMachine::mSMDebug

The patch is exclusively libcwd related.

Turns off output from statemachines to dc::statemachine by default.
Allows to turn on the debug output on a per statemachine basis (at
compile time).

indra/newview/statemachine/aifetchinventoryfolder.cpp

@@ -155,7 +155,7 @@ void AIFetchInventoryFolder::multiplex_impl(state_type run_state)
 		  // Create the folder.
 		  mFolderUUID = gInventory.createNewCategory(mParentFolder, LLFolderType::FT_NONE, mFolderName);
 		  llassert_always(!mFolderUUID.isNull());
-		  Dout(dc::statemachine, "Created folder \"" << mFolderName << "\".");
+		  Dout(dc::statemachine(mSMDebug), "Created folder \"" << mFolderName << "\".");
 		  mNeedNotifyObservers = true;
 		}
 		mCreated = true;