tools/nolibc: tests: constify test_names

Nothing ever modifies this structure.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

tools/testing/selftests/nolibc/nolibc-test.c

@@ -717,7 +717,7 @@ int prepare(void)
 }
 
 /* This is the definition of known test names, with their functions */
-static struct test test_names[] = {
+static const struct test test_names[] = {
 	/* add new tests here */
 	{ .name = "syscall",   .func = run_syscall  },
 	{ .name = "stdlib",    .func = run_stdlib   },