ARM: 8633/1: nommu: allow mmap when !CONFIG_MMU

commit ab6494f0c96f ("nommu: Add noMMU support to the DMA API") have
add CONFIG_MMU compilation flag but that prohibit to use dma_mmap_wc()
when the platform doesn't have MMU.

This patch call vm_iomap_memory() in noMMU case to test if addresses
are correct and set vma->vm_flags rather than all return an error.

Signed-off-by: Benjamin Gaignard <[e-mail]>
Signed-off-by: Russell King <[e-mail]>

arch/arm/mm/dma-mapping.c

···
 				      vma->vm_end - vma->vm_start,
 				      vma->vm_page_prot);
 	}
+#else
+	ret = vm_iomap_memory(vma, vma->vm_start,
+			      (vma->vm_end - vma->vm_start));
 #endif	/* CONFIG_MMU */
 
 	return ret;