selftests/efivarfs: create-read: fix a resource leak

The opened file should be closed in main(), otherwise resource
leak will occur that this problem was discovered by code reading
Signed-off-by: zhujun2 <zhujun2@cmss.chinamobile.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

tools/testing/selftests/efivarfs/create-read.c

@@ -32,8 +32,10 @@ int main(int argc, char **argv)
 	rc = read(fd, buf, sizeof(buf));
 	if (rc != 0) {
 		fprintf(stderr, "Reading a new var should return EOF\n");
+		close(fd);
 		return EXIT_FAILURE;
 	}
 
+	close(fd);
 	return EXIT_SUCCESS;
 }