adbd: only register dnsservices via explicit API

For privacy/security reasons, let's not broadcast the adb secure
services on startup automatically, and instead leave that up to
the rest of the adbd code somehow.

Instead, this CL adds an API in daemon/mdns.h that lets the user
control when registration happens, potentially only doing so if
the developer option is enabled or something.

Bug: 111434128, 119490749

Test: N/A
Exempt-From-Owner-Approval: already approved
Change-Id: Idc994a59ef9e5d48f08796c21989883497e19ef8
diff --git a/adb/daemon/mdns.h b/adb/daemon/mdns.h
index 4c6b1ca..a18093b 100644
--- a/adb/daemon/mdns.h
+++ b/adb/daemon/mdns.h
@@ -19,4 +19,12 @@
 
 void setup_mdns(int port);
 
+void register_adb_secure_pairing_service(int port);
+void unregister_adb_secure_pairing_service(int port);
+bool is_adb_secure_pairing_service_registered();
+
+void register_adb_secure_connect_service(int port);
+void unregister_adb_secure_connect_service(int port);
+bool is_adb_secure_connect_service_registered();
+
 #endif  // _DAEMON_MDNS_H_