[POWERPC] sysdev/mpic_msi.c should include sysdev/mpic.h

Some of the routines defined in mpic_msi.c are declared mpic.h,
so the former should include the latter.

Signed-off-by: Michael Ellerman <[e-mail]>
Signed-off-by: Paul Mackerras <[e-mail]>

arch/powerpc/sysdev/mpic_msi.c

···
 #include <asm/hw_irq.h>
 #include <asm/ppc-pci.h>
 
+#include <sysdev/mpic.h>
 
 static void __mpic_msi_reserve_hwirq(struct mpic *mpic, irq_hw_number_t hwirq)
 {