dialog: Fix missing unlock ops on DB load error-cases

This patch fixes some startup deadlocks in case a dialog loaded from
database has an incorrect DID (failed checksum check) or if OpenSIPS
runs out of shared memory while importing dialogs from DB on startup.

(cherry picked from commit 9e8d36c)

modules/dialog/dlg_db_handler.c

@@ -627,6 +627,7 @@ static int load_dialog_info_from_db(int dlg_hash_size)
 			}
 
 			if(dlg->h_entry != hash_entry){
+				dlg_unlock(d_table, d_entry);
 				LM_ERR("inconsistent hash data in the dialog database: "
 					"you may have restarted opensips using a different "
 					"hash_size: please erase %.*s database and restart\n"
@@ -670,6 +671,7 @@ static int load_dialog_info_from_db(int dlg_hash_size)
 				LM_ERR("dlg_set_leg_info failed\n");
 				/* destroy the dialog */
 				unref_dlg_unsafe(dlg, 1, d_entry);
+				dlg_unlock(d_table, d_entry);
 				continue;
 			}
 			dlg->legs_no[DLG_LEG_200OK] = DLG_FIRST_CALLEE_LEG;
@@ -727,6 +729,7 @@ static int load_dialog_info_from_db(int dlg_hash_size)
 					ZSW(dlg->legs[callee_idx(dlg)].tag.s));
 				/* destroy the dialog */
 				unref_dlg_unsafe(dlg, 1, d_entry);
+				dlg_unlock(d_table, d_entry);
 				continue;
 			}