ARM: dts: msm: Use SMR mask for KGSL SMMU for sdm855

The GPU now generates two SIDs for each context bank
instead of one, one for each TBU. Add support for
using the SMR mask so that we don't run out of SMR
registers due to having twice as many SIDs in use.

Change-Id: I082d338210bbb680502789a15158c8f50726a028
Signed-off-by: Kyle Piefer <kpiefer@codeaurora.org>