ARM: dts: msm: Disable SPI0 and I2C6 on SKUT1 board

As GPIO8 is only used for LCD enabling on SKUT1 board, so
disable the SPI0 which conflicts with it. Also disable I2C6
because it is not used on SKUT1.

Change-Id: I015cb09c7688417b6f39713c1f9ee9d56c3fb864
Signed-off-by: Gustavo Solaira <gustavos@codeaurora.org>