Use the new tlb read hazard macros from <asm/hazards.h> rather than the
local BARRIER() macro which uses 7 ops regardless of the kernel
configuration.

We use mtc0_tlbr_hazard for the hazard between mtc0 to the index
register and the tlbr, and tlb_read_hazard for the hazard between the
tlbr and the mfc0 of the TLB registers written by tlbr.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/10074/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>