drm/etnaviv: move IOMMU domain allocation into etnaviv MMU

The GPU code doesn't need to deal with the IOMMU directly, instead
it can all be hidden behind the etnaviv mmu interface. Move the
last remaining part into etnaviv mmu.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>

drivers/gpu/drm/etnaviv/etnaviv_iommu.c

@@ -219,7 +219,7 @@ void etnaviv_iommuv1_restore(struct etnaviv_gpu *gpu)
 	gpu_write(gpu, VIVS_MC_MMU_RA_PAGE_TABLE, pgtable);
 }
 
-struct iommu_domain *etnaviv_iommu_domain_alloc(struct etnaviv_gpu *gpu)
+struct iommu_domain *etnaviv_iommuv1_domain_alloc(struct etnaviv_gpu *gpu)
 {
 	struct etnaviv_iommu_domain *etnaviv_domain;
 	int ret;