cdrom: fix an incorrect __user annotation on cdrom_sysctl_info

No user pointers for sysctls anymore.

Fixes: 3292739 ("sysctl: pass kernel pointers to ->proc_handler")
Reported-by: build test robot <lkp@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Author: Christoph Hellwig

drivers/cdrom/cdrom.c

@@ -3518,7 +3518,7 @@ static int cdrom_print_info(const char *header, int val, char *info,
 }
 
 static int cdrom_sysctl_info(struct ctl_table *ctl, int write,
-                           void __user *buffer, size_t *lenp, loff_t *ppos)
+                           void *buffer, size_t *lenp, loff_t *ppos)
 {
 	int pos;
 	char *info = cdrom_sysctl_settings.info;