ARM: dts: msm: Disable UARTDM1 core by default

Keep hsuart over uartdm1 core disabled by default.
At present there is no client using the high speed
UART on MSM8939 target.

Change-Id: Ie2c1084ef23b0903524ec625d9d32bef8082a804
Signed-off-by: Dilip Kota <c_dkota@codeaurora.org>