remove stale file from merge

src/passphrase_callback.hh

@@ -1,14 +0,0 @@
-#pragma once
-#include <pEp/passphrase_cache.hh>
-
-
-namespace pEp {
-    namespace JNIAdapter {
-
-        char* passphraseRequiredCallback(const PEP_STATUS status);
-
-        template<typename... A> PEP_STATUS passphraseWrap(PEP_STATUS f(PEP_SESSION, A...), PEP_SESSION session, A... a);
-    }
-}
-
-#include "passphrase_callback.hxx"