x86: get rid of pt_regs argument of iopl(2)

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

arch/x86/kernel/ioport.c

@@ -93,8 +93,9 @@ asmlinkage long sys_ioperm(unsigned long from, unsigned long num, int turn_on)
  * on system-call entry - see also fork() and the signal handling
  * code.
  */
-long sys_iopl(unsigned int level, struct pt_regs *regs)
+SYSCALL_DEFINE1(iopl, unsigned int, level)
 {
+	struct pt_regs *regs = current_pt_regs();
 	unsigned int old = (regs->flags >> 12) & 3;
 	struct thread_struct *t = &current->thread;