ARM: dts: msm: Enable mpu6880 accel+gyro for MSM8916 SKUT2

Add mpu6880 6-axis accelerometer+gyro sensor to
the MSM8916 SKUT2 device tree. It uses the mpu6050
driver because they are compatible.

Change-Id: I5fcf0d45193cc1192c35f007e30377c7c9445588
Signed-off-by: Gustavo Solaira <gustavos@codeaurora.org>