powerpc/47x: Add an isync before the tlbivax instruction

Signed-off-by: NDave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: NJosh Boyer <jwboyer@linux.vnet.ibm.com>

arch/powerpc/mm/tlb_nohash_low.S

@@ -200,6 +200,7 @@ _GLOBAL(_tlbivax_bcast)
 	rlwimi	r5,r4,0,16,31
 	wrteei	0
 	mtspr	SPRN_MMUCR,r5
+	isync
 /*	tlbivax	0,r3 - use .long to avoid binutils deps */
 	.long 0x7c000624 | (r3 << 11)
 	isync