serial: 8250: lock port for stop_rx() in omap8250_irq()

serial: 8250: lock port for stop_rx() in omap8250_irq()

[ Upstream commit ca73a892c5bec4b08a2fa22b3015e98ed905abb7 ]

The uarts_ops stop_rx() callback expects that the port->lock is
taken and interrupts are disabled.

Fixes: 1fe0e1fa3209 ("serial: 8250_omap: Handle optional overrun-throttle-ms property")
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20230525093159.223817-4-john.ogness@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>