tools: Fix compiler warning in idevicepair
diff --git a/tools/idevicepair.c b/tools/idevicepair.c
index 65a7317..4647d6f 100644
--- a/tools/idevicepair.c
+++ b/tools/idevicepair.c
@@ -110,7 +110,7 @@
 			free(xml);
 		}
 	} else if (cb_type == LOCKDOWN_CU_PAIRING_ERROR) {
-		printf("ERROR: %s\n", (data_ptr) ? data_ptr : "(unknown)");
+		printf("ERROR: %s\n", (data_ptr) ? (char*)data_ptr : "(unknown)");
 	}
 }