dm: test: Add a new test case for dm_test_eth_rotate

Add one more ethernet device node in the sandbox test device tree,
with name 'sbe5'. This is to support a new test case for testing
network device rotation.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>

test/dm/eth.c

@@ -106,6 +106,11 @@ static int _dm_test_eth_rotate2(struct unit_test_state *uts)
 	ut_assertok(net_loop(PING));
 	ut_asserteq_str("eth@10004000", getenv("ethact"));
 
+	/* Make sure we can handle device name which is not eth# */
+	setenv("ethact", "sbe5");
+	ut_assertok(net_loop(PING));
+	ut_asserteq_str("sbe5", getenv("ethact"));
+
 	return 0;
 }