ARM: 5796/1: SA1100: h3600: remove IRDA bits from serial PM callback

IRDA is handled by separate sa1100-ir driver and has
nothing to do with sa1100_serial

Signed-off-by: Dmitry Artamonow <mad_soft@inbox.ru>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>