example: use `git_off_t` for the object size

examples/blame.c

@@ -33,7 +33,7 @@ static void parse_opts(struct opts *o, int argc, char *argv[]);
 int lg2_blame(git_repository *repo, int argc, char *argv[])
 {
 	int line, break_on_null_hunk;
-	size_t i, rawsize;
+	git_off_t i, rawsize;
 	char spec[1024] = {0};
 	struct opts o = {0};
 	const char *rawdata;