[POWERPC] 40x MMU

Add MMU definitions for 40x platforms.  Also fixes two warnings in 40x_mmu.c.

Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>

arch/powerpc/kernel/head_40x.S

@@ -772,7 +772,7 @@ finish_tlb_load:
 	*/
 	lwz	r9, tlb_4xx_index@l(0)
 	addi	r9, r9, 1
-	andi.	r9, r9, (PPC4XX_TLB_SIZE-1)
+	andi.	r9, r9, (PPC40X_TLB_SIZE-1)
 	stw	r9, tlb_4xx_index@l(0)
 
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