Move get_my_privkey into Musig2

Author: hacpy

musig2/src/main/java/com/chainx/musig2bitcoin/Musig2.java

@@ -6,7 +6,9 @@ public class Musig2 {
     static {
         System.loadLibrary("musig2_dll");
     }
-    
+
+    public static native String get_my_privkey(String phrase, String pd_passphrase);
+
     public static native String get_my_pubkey(String jarg1);
 
     public static native long get_round1_state();
@@ -23,6 +25,10 @@ public class Musig2 {
 
     public static native String get_key_agg(String jarg1);
 
+    public static String getMyPrivkey(String phrase, String pd_passphrase) {
+      return  get_my_privkey(phrase, pd_passphrase);
+    };
+
     public static String getMyPubkey(String priv) {
         return get_my_pubkey(priv);
     };

musig2/src/main/java/com/chainx/musig2bitcoin/Transaction.java

@@ -28,8 +28,6 @@ public static native String build_raw_script_tx(String base_tx,
 
     public static native String generate_schnorr_signature(String message, String privkey);
 
-    public static native String get_my_privkey(String phrase, String pd_passphrase);
-
     public static native String get_script_pubkey(String addr);
 
     public static native String get_spent_outputs(String prev_tx, long input_index);