random: fix an incorrect __user annotation on proc_do_entropy

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/char/random.c

@@ -2087,7 +2087,7 @@ static int proc_do_uuid(struct ctl_table *table, int write,
  * Return entropy available scaled to integral bits
  */
 static int proc_do_entropy(struct ctl_table *table, int write,
-			   void __user *buffer, size_t *lenp, loff_t *ppos)
+			   void *buffer, size_t *lenp, loff_t *ppos)
 {
 	struct ctl_table fake_table;
 	int entropy_count;