drivers: clean-up prom.h implicit includes

Powerpc is a mess of implicit includes by prom.h. Add the necessary
explicit includes to drivers in preparation of prom.h cleanup.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Grant Likely <grant.likely@linaro.org>
diff --git a/drivers/macintosh/via-pmu.c b/drivers/macintosh/via-pmu.c
index 283e1b5..dee88e5 100644
--- a/drivers/macintosh/via-pmu.c
+++ b/drivers/macintosh/via-pmu.c
@@ -46,6 +46,8 @@
 #include <linux/suspend.h>
 #include <linux/cpu.h>
 #include <linux/compat.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
 #include <asm/prom.h>
 #include <asm/machdep.h>
 #include <asm/io.h>