clk: pxa: add missing pxa27x clocks for Irda and sa1100-rtc

Add 2 clocks which were erronously forgotten by the clock framework
port, namely :
 - sa1100-rtc
 - irda for pxa2xx-ir:UARTCLK

Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Acked-by: Michael Turquette <mturquette@linaro.org>