msm: ultrasound: support up to eight TX and RX channels

Ultrasound digital pen service requires six TX channels for
the service performance improvement.

Change-Id: Id01f9cf2c9df6a55a72bfa395ffe1c2e85d8cdc7
Signed-off-by: Ravit Dennis <rdennis@codeaurora.org>
Linux 3.4.80

Signed-off-by: houst0nn <houstonn@gmail.com>

Conflicts:
	drivers/iommu/intel-iommu.c
ditch -Wall to suppress warnings

Signed-off-by: houst0nn <houstonn@gmail.com>