iommu/arm-smmu-qcom: Implement S2CR quirk

The firmware found in some Qualcomm platforms intercepts writes to S2CR
in order to replace bypass type streams with fault; and ignore S2CR
updates of type fault.

Detect this behavior and implement a custom write_s2cr function in order
to trick the firmware into supporting bypass streams by the means of
configuring the stream for translation using a reserved and disabled
context bank.

Also circumvent the problem of configuring faulting streams by
configuring the stream as bypass.

Cc: <[email protected]>
Signed-off-by: Bjorn Andersson <[email protected]>
Tested-by: Steev Klimaszewski <[email protected]>
Acked-by: Robin Murphy <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Will Deacon <[email protected]>

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