ARM: dts: msm: Exclude Q6 SMEM region from AQC IOVA space

When DMA memory IOVA allocated for AQC falls within Q6 SMEM PHYS region,
mapping it symmetrically to IPA would remove Q6 SMEM region already
mapped into IPA. Reduce IOVA space used by AQC to exclude the Q6 SMEM
region.

Change-Id: I8335586e88d2f16f702b88b90723da6014d113c5
Signed-off-by: Jinesh K. Jayakumar <jineshk@codeaurora.org>