include/linux/llist.h: 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.

Link: https://lkml.kernel.org/r/20211013170417.87909-6-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Brendan Higgins <brendanhiggins@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Cameron <jic23@kernel.org>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thorsten Leemhuis <regressions@leemhuis.info>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

include/linux/llist.h

@@ -49,7 +49,9 @@
  */
 
 #include <linux/atomic.h>
-#include <linux/kernel.h>
+#include <linux/container_of.h>
+#include <linux/stddef.h>
+#include <linux/types.h>
 
 struct llist_head {
 	struct llist_node *first;