ARM: dts: msm: specify UART5 configuration for MDM9607 platform

MDM9607 has CMUX use case on UART5 and hence enable the dtsi
configuration with status disabled so that client can enable
based on need.

Change-Id: I250f332ca31559b7804d60a9afe1ccfd1db353cb
Signed-off-by: Mukesh Kumar Savaliya <msavaliy@codeaurora.org>