Re-enable the apps_smmu now that the arm-smmu driver supports stream
mapping handoff from firmware.

Tested-by: Steev Klimaszewski <steev@kali.org>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Link: https://lore.kernel.org/r/20201124184414.380796-1-bjorn.andersson@linaro.org


Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>