MIPS: hugetlbfs: Fix hazard between tlb write and pagemask restoration.

On some CPU the write to pagemask might complete before the TLB write
instruction reads from the pagemask register.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

arch/mips/mm/tlb-r4k.c

@@ -320,6 +320,7 @@ void __update_tlb(struct vm_area_struct * vma, unsigned long address, pte_t pte)
 			tlb_write_random();
 		else
 			tlb_write_indexed();
+		tlbw_use_hazard();
 		write_c0_pagemask(PM_DEFAULT_MASK);
 	} else
 #endif