powerpc: Remove unnecessary casts of void ptr

Hi,

The [vk][cmz]alloc(_node) family of functions return void pointers which
it's completely unnecessary/pointless to cast to other pointer types since
that happens implicitly.

This patch removes such casts from arch/powerpc/
Signed-off-by: NJesper Juhl <jj@chaosbits.net>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

arch/powerpc/mm/pgtable_32.c

@@ -78,7 +78,7 @@ pgd_t *pgd_alloc(struct mm_struct *mm)
 
 	/* pgdir take page or two with 4K pages and a page fraction otherwise */
 #ifndef CONFIG_PPC_4K_PAGES
-	ret = (pgd_t *)kzalloc(1 << PGDIR_ORDER, GFP_KERNEL);
+	ret = kzalloc(1 << PGDIR_ORDER, GFP_KERNEL);
 #else
 	ret = (pgd_t *)__get_free_pages(GFP_KERNEL|__GFP_ZERO,
 			PGDIR_ORDER - PAGE_SHIFT);