[ARM] pxa: move pmu device back into mach-pxa/

Not tested and enabled on MMP at this moment, and since the IRQ
is different from mach-pxa, I'd prefer to move the PMU device
back into mach-pxa/. Will introduce the PMU device to MMP once
it's enabled and tested.

Signed-off-by: Eric Miao <eric.y.miao@gmail.com>
diff --git a/arch/arm/mach-pxa/pxa3xx.c b/arch/arm/mach-pxa/pxa3xx.c
index c18d2df..acfa9f7 100644
--- a/arch/arm/mach-pxa/pxa3xx.c
+++ b/arch/arm/mach-pxa/pxa3xx.c
@@ -608,6 +608,7 @@
 
 static struct platform_device *devices[] __initdata = {
 	&pxa27x_device_udc,
+	&pxa_device_pmu,
 	&pxa_device_i2s,
 	&sa1100_device_rtc,
 	&pxa_device_rtc,