powerpc/powernv/npu: Use flush_all_mm() instead of flush_tlb_mm()

With the optimisations introduced by commit a46cc7a908 ("powerpc/mm/radix:
Improve TLB/PWC flushes"), flush_tlb_mm() no longer flushes the page walk
cache with radix. Switch to using flush_all_mm() to ensure the pwc and tlb
are properly flushed on the nmmu.
Signed-off-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/platforms/powernv/npu-dma.c

@@ -549,7 +549,7 @@ static void mmio_invalidate(struct npu_context *npu_context, int va,
 	 * Unfortunately the nest mmu does not support flushing specific
 	 * addresses so we have to flush the whole mm.
 	 */
-	flush_tlb_mm(npu_context->mm);
+	flush_all_mm(npu_context->mm);
 
 	/*
 	 * Loop over all the NPUs this process is active on and launch