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>

[poondog: modify for flo]
Signed-off-by: poondog <markj338@gmail.com>
msm: ultrasound: Add a new input device configuration

Add a new input device configuration in order to
support an external display.

Change-Id: I0acca1324013a7bd812857aea715f204f5e3c005
Signed-off-by: Ravit Dennis <rdennis@codeaurora.org>
Signed-off-by: poondog <markj338@gmail.com>
msm: ultrasound: Support side buttons

Add new button notifications in order to be
able to report stylus side button states.

Change-Id: I49598b4aab23ff1e041257640d8f63e2da3dd554
Signed-off-by: Ravit Dennis <rdennis@codeaurora.org>
Signed-off-by: poondog <markj338@gmail.com>