kernel: Remove unnecessary inclusions of asm/semaphore.h

None of these files use any of the functionality promised by
asm/semaphore.h.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>

kernel/kexec.c

@@ -29,7 +29,6 @@
 #include <asm/uaccess.h>
 #include <asm/io.h>
 #include <asm/system.h>
-#include <asm/semaphore.h>
 #include <asm/sections.h>
 
 /* Per cpu memory for storing cpu states in case of system crash. */

kernel/kthread.c

@@ -13,7 +13,6 @@
 #include <linux/file.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
-#include <asm/semaphore.h>
 
 #define KTHREAD_NICE_LEVEL (-5)
 

kernel/module.c

@@ -43,7 +43,6 @@
 #include <linux/mutex.h>
 #include <linux/unwind.h>
 #include <asm/uaccess.h>
-#include <asm/semaphore.h>
 #include <asm/cacheflush.h>
 #include <linux/license.h>
 #include <asm/sections.h>
@@ -664,7 +663,7 @@ static void free_module(struct module *mod);
 
 static void wait_for_zero_refcount(struct module *mod)
 {
-	/* Since we might sleep for some time, drop the semaphore first */
+	/* Since we might sleep for some time, release the mutex first */
 	mutex_unlock(&module_mutex);
 	for (;;) {
 		DEBUGP("Looking at refcount...\n");

kernel/posix-timers.c

@@ -37,7 +37,6 @@
 #include <linux/mutex.h>
 
 #include <asm/uaccess.h>
-#include <asm/semaphore.h>
 #include <linux/list.h>
 #include <linux/init.h>
 #include <linux/compiler.h>

kernel/profile.c

@@ -23,7 +23,6 @@
 #include <linux/highmem.h>
 #include <linux/mutex.h>
 #include <asm/sections.h>
-#include <asm/semaphore.h>
 #include <asm/irq_regs.h>
 #include <asm/ptrace.h>
 

kernel/stop_machine.c

@@ -11,7 +11,6 @@
 #include <linux/interrupt.h>
 
 #include <asm/atomic.h>
-#include <asm/semaphore.h>
 #include <asm/uaccess.h>
 
 /* Since we effect priority and affinity (both of which are visible