Revert "device property: Keep secondary firmware node secondary by type"

stable inclusion
from stable-5.10.7
commit 6844bc38c9fe5c20994f4a0819eac1fc9acd80eb
bugzilla: 47429

--------------------------------

commit 47f44699 upstream.

While commit d5dcce0c ("device property: Keep secondary firmware
node secondary by type") describes everything correct in its commit
message, the change it made does the opposite and original commit
c15e1bdd ("device property: Fix the secondary firmware node handling
in set_primary_fwnode()") was fully correct.

Revert the former one here and improve documentation in the next patch.

Fixes: d5dcce0c ("device property: Keep secondary firmware node secondary by type")
Signed-off-by: NBard Liao <yung-chuan.liao@linux.intel.com>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Cc: 5.10+ <stable@vger.kernel.org> # 5.10+
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NChen Jun <chenjun102@huawei.com>
Acked-by: NXie XiuQi <xiexiuqi@huawei.com>

drivers/base/core.c

@@ -4278,7 +4278,7 @@ void set_primary_fwnode(struct device *dev, struct fwnode_handle *fwnode)
 		if (fwnode_is_primary(fn)) {
 			dev->fwnode = fn->secondary;
 			if (!(parent && fn == parent->fwnode))
-				fn->secondary = ERR_PTR(-ENODEV);
+				fn->secondary = NULL;
 		} else {
 			dev->fwnode = NULL;
 		}