Fix a couple of warnings

src/remote.c

@@ -914,7 +914,7 @@ static int rename_one_remote_reference(
 	const char *old_remote_name,
 	const char *new_remote_name)
 {
-	int error;
+	int error = -1;
 	git_buf new_name = GIT_BUF_INIT;
 	git_reference *reference = NULL;
 

tests-clar/stash/foreach.c

@@ -39,10 +39,11 @@ static int callback_cb(
 		const git_oid *stash_oid,
 		void *payload)
 {
-	int i = 0;
-	bool found = false;
 	struct callback_data *data = (struct callback_data *)payload;
 
+	GIT_UNUSED(index);
+	GIT_UNUSED(message);
+
 	cl_assert_equal_i(0, git_oid_streq(stash_oid, data->oids[data->invokes++]));
 	
 	return 0;

tests-clar/stash/stash_helpers.c

 #include "clar_libgit2.h"
 #include "fileops.h"
+#include "stash_helpers.h"
 
 void commit_staged_files(
 	git_oid *commit_oid,