resolved: move DNS RR/key/answer/question/packet tools to shared/

We want to reuse these generic DNS concepts in resolved hook
implementations, hence move them to shared code.

(This also enables us to immediately remove som SVCB record handling
duplicate definitions.)

No real code changes, just some moving around of things.

src/resolve/resolvectl.c

@@ -22,6 +22,8 @@
 #include "bus-message-util.h"
 #include "bus-util.h"
 #include "dns-domain.h"
+#include "dns-packet.h"
+#include "dns-rr.h"
 #include "errno-list.h"
 #include "errno-util.h"
 #include "escape.h"
@@ -42,8 +44,6 @@
 #include "resolve-util.h"
 #include "resolvectl.h"
 #include "resolved-def.h"
-#include "resolved-dns-packet.h"
-#include "resolved-dns-rr.h"
 #include "resolved-util.h"
 #include "socket-netlink.h"
 #include "sort-util.h"