parisc: Avoid function pointers for kernel exception routines

We want to avoid the kernel module loader to create function pointers
for the kernel fixup routines of get_user() and put_user(). Changing
the external reference from function type to int type fixes this.

This unbreaks exception handling for get_user() and put_user() when
called from a kernel module.

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org