powerpc: Ensure global functions include their prototype

Fix a number of places where global functions were not including
their prototype. This ensures the prototype and the function match.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
diff --git a/arch/powerpc/mm/slice.c b/arch/powerpc/mm/slice.c
index b0c75cc..86f6a75 100644
--- a/arch/powerpc/mm/slice.c
+++ b/arch/powerpc/mm/slice.c
@@ -30,9 +30,11 @@
 #include <linux/err.h>
 #include <linux/spinlock.h>
 #include <linux/export.h>
+#include <linux/hugetlb.h>
 #include <asm/mman.h>
 #include <asm/mmu.h>
 #include <asm/spu.h>
+#include <asm/hugetlb.h>
 
 /* some sanity checks */
 #if (PGTABLE_RANGE >> 43) > SLICE_MASK_SIZE