move memory_read_from_buffer() from fs.h to string.h

James Bottomley warns that inclusion of linux/fs.h in a low level
driver was always a danger signal. This patch moves
memory_read_from_buffer() from fs.h to string.h and fixes includes in
existing memory_read_from_buffer() users.

Signed-off-by: Akinobu Mita <[e-mail]>
Cc: James Bottomley <[e-mail]>
Cc: Geert Uytterhoeven <[e-mail]>
Cc: Zhang Rui <[e-mail]>
Cc: Bob Moore <[e-mail]>
Cc: Thomas Renninger <[e-mail]>
Cc: Len Brown <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

drivers/acpi/system.c

···
 #include <linux/proc_fs.h>
 #include <linux/seq_file.h>
 #include <linux/init.h>
+#include <linux/string.h>
 #include <asm/uaccess.h>
 
 #include <acpi/acpi_drivers.h>

drivers/zorro/zorro-sysfs.c

···
 #include <linux/zorro.h>
 #include <linux/stat.h>
 #include <linux/string.h>
-#include <linux/fs.h>
 
 #include "zorro.h"
 

include/linux/fs.h

···
 
 extern ssize_t simple_read_from_buffer(void __user *to, size_t count,
 			loff_t *ppos, const void *from, size_t available);
-extern ssize_t memory_read_from_buffer(void *to, size_t count, loff_t *ppos,
-			const void *from, size_t available);
 
 #ifdef CONFIG_MIGRATION
 extern int buffer_migrate_page(struct address_space *,

include/linux/string.h

···
 
 extern bool sysfs_streq(const char *s1, const char *s2);
 
+extern ssize_t memory_read_from_buffer(void *to, size_t count, loff_t *ppos,
+			const void *from, size_t available);
+
 #endif
 #endif /* _LINUX_STRING_H_ */