pki: Use a consistent name scheme.

Rename ssh_key_import_private to ssh_pki_import_privkey_file.

include/libssh/libssh.h

@@ -429,7 +429,7 @@ LIBSSH_API int ssh_pki_import_privkey_base64(ssh_session session,
                                              const char *b64_key,
                                              const char *passphrase,
                                              ssh_key *pkey);
-LIBSSH_API int ssh_key_import_private(ssh_session session,
+LIBSSH_API int ssh_pki_import_privkey_file(ssh_session session,
                                       const char *filename,
                                       const char *passphrase,
                                       ssh_key *pkey);

src/bind.c

@@ -309,7 +309,7 @@ int ssh_bind_accept(ssh_bind sshbind, ssh_session session) {
   }
 
   if (sshbind->dsakey) {
-      rc = ssh_key_import_private(session, sshbind->dsakey, NULL, &dsa);
+      rc = ssh_pki_import_privkey_file(session, sshbind->dsakey, NULL, &dsa);
       if (rc == SSH_ERROR) {
           return SSH_ERROR;
       }
@@ -321,7 +321,7 @@ int ssh_bind_accept(ssh_bind sshbind, ssh_session session) {
   }
 
   if (sshbind->rsakey) {
-      rc = ssh_key_import_private(session, sshbind->rsakey, NULL, &rsa);
+      rc = ssh_pki_import_privkey_file(session, sshbind->rsakey, NULL, &rsa);
       if (rc == SSH_ERROR) {
           return SSH_ERROR;
       }

src/legacy.c

@@ -274,7 +274,7 @@ ssh_private_key privatekey_from_file(ssh_session session,
 
     (void) type; /* unused */
 
-    rc = ssh_key_import_private(session, filename, passphrase, &key);
+    rc = ssh_pki_import_privkey_file(session, filename, passphrase, &key);
     if (rc == SSH_ERROR) {
         return NULL;
     }

src/pki.c

@@ -200,16 +200,24 @@ int ssh_key_is_private(ssh_key k) {
 }
 
 /**
- * @brief import a key from a file
+ * @brief Import a key from a file.
- * @param[out]  key      the ssh_key to update
+ *
- * @param[in]  session  The SSH Session to use. If a key decryption callback is set, it will
+ * @param[in]  session  The SSH Session to use. If a authentication callback is
- *                      be used to ask for the passphrase.
+ *                      set, it will be used to ask for the passphrase.
+ *
  * @param[in]  filename The filename of the the private key.
- * @param[in]  passphrase The passphrase to decrypt the private key. Set to null
+ *
+ * @param[in]  passphrase The passphrase to decrypt the private key. Set to NULL
  *                        if none is needed or it is unknown.
+ *
+ * @param[out] pkey     A pointer to store the ssh_key. You need to free the
+ *                      key.
+ *
  * @returns SSH_OK on success, SSH_ERROR otherwise.
+ *
+ * @see ssh_key_free()
  **/
-int ssh_key_import_private(ssh_session session,
+int ssh_pki_import_privkey_file(ssh_session session,
                                 const char *filename,
                                 const char *passphrase,
                                 ssh_key *pkey) {