parisc: Export iosapic_serial_irq() symbol for serial port driver

stable inclusion
from stable-v5.10.154
commit 98f836e80d210312ec98ffbbce4a0b6c4b6dc34e
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I64YCB

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=98f836e80d210312ec98ffbbce4a0b6c4b6dc34e



--------------------------------

commit a0c9f1f2 upstream.

The parisc serial port driver needs this symbol when it's compiled
as module.

Signed-off-by: Helge Deller <deller@gmx.de>
Reported-by: kernel test robot <lkp@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Lipeng Sang <sanglipeng1@jd.com>