arm64: Use swiotlb late initialisation

arm64: Use swiotlb late initialisation

Since arm64 does not support ISA, there is no need for early swiotlb
initialisation. This patch switches the DMA mapping code to
swiotlb_tlb_late_init_with_default_size(). A side effect of this is that
GFP_DMA is used for the swiotlb buffer and devices with a 32-bit
coherent mask are correctly supported.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit 3690951fc6d42f3a0903987677d0e592c49dd8db)
Signed-off-by: Ryan Harkin <ryan.harkin@linaro.org>
Conflicts:
	arch/arm64/mm/init.c
Signed-off-by: Mark Brown <broonie@linaro.org>