kobject: Replace kernel.h with the necessary inclusions

When kernel.h is used in the headers it adds a lot into dependency hell,
especially when there are circular dependencies are involved.

Replace kernel.h inclusion with the list of what is really being used.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20211110103128.59888-1-andriy.shevchenko@linux.intel.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

include/linux/kobject.h

@@ -19,10 +19,10 @@
 #include <linux/list.h>
 #include <linux/sysfs.h>
 #include <linux/compiler.h>
+#include <linux/container_of.h>
 #include <linux/spinlock.h>
 #include <linux/kref.h>
 #include <linux/kobject_ns.h>
-#include <linux/kernel.h>
 #include <linux/wait.h>
 #include <linux/atomic.h>
 #include <linux/workqueue.h>