Revert "iommu/dma: Force swiotlb_max_mapping_size on an untrusted device"

This reverts commit 2280bb85 which is
commit afc5aa46 upstream.

It breaks the Android kernel abi and can be brought back in the future
in an abi-safe way if it is really needed.

Bug: 161946584
Change-Id: I3488e3d72a08365b8c79b49ea198682947d3ad8e
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>