ipmi: explicitly include of_address.h and of_irq.h

of_address.h and of_irq.h are implicitly included on powerpc. Adding
them fixes builds on non-powerpc platforms.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

drivers/char/ipmi/ipmi_si_intf.c

@@ -69,6 +69,8 @@
 #ifdef CONFIG_PPC_OF
 #include <linux/of_device.h>
 #include <linux/of_platform.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
 #endif
 
 #define PFX "ipmi_si: "