sched/headers: Remove <linux/rwsem.h> from <linux/sched.h>

This is a stray header that is not needed by anything in sched.h,
so remove it.

Update files that relied on the stray inclusion.

This reduces the size of the header dependency graph.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

include/linux/sched.h

@@ -226,8 +226,6 @@ struct task_cputime {
 #define prof_exp	stime
 #define sched_exp	sum_exec_runtime
 
-#include <linux/rwsem.h>
-
 #ifdef CONFIG_SCHED_INFO
 struct sched_info {
 	/* cumulative counters */

include/linux/user_namespace.h

@@ -5,6 +5,7 @@
 #include <linux/nsproxy.h>
 #include <linux/ns_common.h>
 #include <linux/sched.h>
+#include <linux/rwsem.h>
 #include <linux/sysctl.h>
 #include <linux/err.h>
 

kernel/utsname_sysctl.c

@@ -14,6 +14,7 @@
 #include <linux/utsname.h>
 #include <linux/sysctl.h>
 #include <linux/wait.h>
+#include <linux/rwsem.h>
 
 #ifdef CONFIG_PROC_SYSCTL