powerpc/44x: Fix ocm_block allocation

Allocate enough memory for the ocm_block structure, not just a pointer
to it.
Signed-off-by: Ilia Mirkin <imirkin@alum.mit.edu>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

arch/powerpc/sysdev/ppc4xx_ocm.c

@@ -339,7 +339,7 @@ void *ppc4xx_ocm_alloc(phys_addr_t *phys, int size, int align,
 		if (IS_ERR_VALUE(offset))
 			continue;
 
-		ocm_blk = kzalloc(sizeof(struct ocm_block *), GFP_KERNEL);
+		ocm_blk = kzalloc(sizeof(struct ocm_block), GFP_KERNEL);
 		if (!ocm_blk) {
 			printk(KERN_ERR "PPC4XX OCM: could not allocate ocm block");
 			rh_free(ocm_reg->rh, offset);