move-only: move warnings from common to node

Since rpc/util.cpp is in common, also move GetNodeWarnings() to
node::GetWarningsForRPC()

src/node/kernel_notifications.cpp

@@ -13,12 +13,12 @@
 #include <logging.h>
 #include <node/abort.h>
 #include <node/interface_ui.h>
+#include <node/warnings.h>
 #include <util/check.h>
 #include <util/signalinterrupt.h>
 #include <util/strencodings.h>
 #include <util/string.h>
 #include <util/translation.h>
-#include <warnings.h>
 
 #include <cstdint>
 #include <string>
@@ -49,7 +49,7 @@ static void AlertNotify(const std::string& strMessage)
 static void DoWarning(const bilingual_str& warning)
 {
     static bool fWarned = false;
-    SetMiscWarning(warning);
+    node::SetMiscWarning(warning);
     if (!fWarned) {
         AlertNotify(warning.original);
         fWarned = true;